# CommandSection

title: CAVEATS
content:
<i>rz</i> requires a compatible Zmodem sender (like <i>sz</i>) on the remote end.<br><br>It primarily operates over serial connections or pseudo-terminals that correctly handle binary data and control characters. Modern environments often use SSH/SFTP for file transfers, making <i>rz</i>/<i>sz</i> less common for general-purpose use over IP networks, though still invaluable for serial console access.<br><br>Security considerations: Transferring files with <i>rz</i> typically does not involve encryption unless the underlying serial connection or terminal session is already encrypted (e.g., via SSH).


title: PROTOCOL DETAILS
content:
<i>rz</i> defaults to the Zmodem protocol, which is generally preferred over Xmodem and Ymodem due to its better error detection, automatic recovery from dropped connections, and ability to transfer multiple files or directories in a single session. It can fallback or be forced to Xmodem using the <b>-X</b> option.


title: TYPICAL USAGE
content:
A common scenario involves logging into a remote system via a serial console (e.g., <i>/dev/ttyS0</i> or <i>/dev/ttyUSB0</i>) or an SSH session where direct <i>scp</i> or <i>sftp</i> might be unavailable or cumbersome.<br><br>The user would then run <i>rz</i> on the remote end, and <i>sz &lt;files&gt;</i> on their local machine, or vice versa, to initiate the transfer. Many terminal emulators have built-in Zmodem support that can automatically detect <i>rz</i> or <i>sz</i> prompts and handle the transfer seamlessly.


title: HISTORY
content:
The <i>rz</i>/<i>sz</i> utilities are part of the <i>lrzsz</i> package, which implements the Zmodem, Ymodem, and Xmodem file transfer protocols. These protocols were widely used in the BBS (Bulletin Board System) era and over dial-up modems for reliable file transfers, especially Zmodem with its error recovery and batch capabilities.<br><br>The original <i>rz</i> and <i>sz</i> programs were developed by Chuck Forsberg. The <i>lrzsz</i> project is a free software port of these utilities to Linux and Unix-like systems, maintaining compatibility and adding enhancements.<br><br>Despite the rise of network-based file transfer protocols like SFTP and SCP, <i>rz</i> and <i>sz</i> remain crucial tools for interacting with serial consoles, embedded systems, or legacy hardware where a full network stack might not be available or practical. Their simplicity and robust error handling make them invaluable in such niche but important scenarios.


title: SEE ALSO
content:
<b>sz</b>(1), <b>sb</b>(1), <b>rb</b>(1), <b>sx</b>(1), <b>rx</b>(1), <b>lrzsz</b>(1), <b>ssh</b>(1), <b>scp</b>(1), <b>sftp</b>(1)


title: SYNOPSIS
content:
<I>Not applicable as 's' is not a standard command.</I><br>The syntax for a custom 's' command would depend entirely on its definition (e.g., alias, shell function, or script) within a specific environment. Therefore, no universal synopsis can be provided.


title: PARAMETERS
content:
<b><I>N/A</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;<I>As 's' is not a standard command, it does not have predefined parameters. Any parameters it accepts would be determined by its custom definition (e.g., if it's an alias for 'ls -l', then it would accept 'ls' parameters).</I><br><br>


title: DESCRIPTION
content:
<I>The command 's' is not a standard or commonly recognized built-in Linux command or utility.</I><br><br>Users might encounter 's' in various contexts, but it's typically an <B>alias</B>, a <B>shell function</B>, or a <B>custom script</B> created by a user or system administrator. For example, 's' is sometimes aliased to 'sudo' or 'ls' in some personal shell configurations for convenience. Without specific context, it's impossible to determine the exact functionality of 's' as it depends entirely on how it has been defined in a particular environment.<br><br>If you encountered 's' and it performed a specific action, it's crucial to check the shell configuration files (like <I>.bashrc</I>, <I>.zshrc</I>, or global shell configuration files) to understand its definition. You can often use commands like <I>type s</I> or <I>alias s</I> in your shell to see if it's an alias or function.


title: CAVEATS
content:
<ul><li><I>Non-Standard:</I> 's' is not part of standard Linux distributions or POSIX specifications. Its presence indicates a local customization.</li><li><I>Context-Dependent:</I> Its behavior is entirely dependent on how it's defined (e.g., alias, shell function, or script) in a specific user's or system's environment. It will likely behave differently or not exist on another system.</li><li><I>Potential for Conflict:</I> Creating a custom 's' might conflict with future standard commands or scripts, although 's' itself is unlikely to become a standard command name.</li><li><I>Security Risk:</I> If you encounter 's' in an unfamiliar environment, always verify its definition before executing it, as it could be a malicious script or alias designed to perform unintended actions.</li></ul>


title: CHECKING 'S' DEFINITION
content:
If you encounter 's' and wish to know what it does, you can use the <I>type</I> command in your shell. For example, entering <I>type s</I> will reveal if 's' is an alias, a function, a built-in command, or an executable file. If it's an alias or function, it will often display its exact definition, such as <I>s is aliased to `sudo`</I> or <I>s is a function s() { ... }</I>.


title: CREATING A CUSTOM 'S' COMMAND
content:
Users can create their own 's' command by adding an alias or a shell function definition to their shell configuration file (e.g., <I>~/.bashrc</I> for Bash, <I>~/.zshrc</I> for Zsh). For example, to alias 's' to 'sudo', you would add the line <I>alias s='sudo'</I> to your <I>.bashrc</I> file. After saving, you'd typically run <I>source ~/.bashrc</I> or restart your shell for the change to take effect. Similarly, a shell function could be defined for more complex logic.


title: HISTORY
content:
<I>There is no official development history for a standard 's' Linux command, as it does not exist as a standalone utility or program in mainstream Linux distributions or POSIX specifications.</I><br><br>The concept of 's' being used as a command would stem purely from individual user practices of creating short aliases or simple scripts for personal convenience and efficiency. This practice of customizing shell environments is as old as shell scripting itself, where users personalize their workflow to reduce typing and improve productivity.


title: SEE ALSO
content:
<I>type(1)</I> (to check if 's' is an alias, function, or built-in in your shell), <I>alias(1)</I> (to list or define aliases in your shell), <I>source(1)</I> (to load shell configuration files where 's' might be defined), <I>ls(1)</I> (a common command sometimes aliased to 's' for listing directory contents), <I>sudo(8)</I> (another common command sometimes aliased to 's' for executing commands with superuser privileges), <I>ss(8)</I> (Socket Statistics, a standard network utility for examining socket connections)


title: PARAMETERS
content:
<b>-connect <I>host</I>:<I>port</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the remote host and port to connect to. This is typically the first and most essential option.<br><br><b>-cert <I>filename</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the client certificate file to use for client authentication.<br><br><b>-key <I>filename</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the private key file corresponding to the client certificate.<br><br><b>-CAfile <I>filename</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;A file containing trusted CA certificates in PEM format. Used to verify the server's certificate.<br><br><b>-CApath <I>directory</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;A directory containing trusted CA certificates in PEM format, hashed by subject. Used to verify the server's certificate.<br><br><b>-verify <I>depth</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets the verification depth for the server's certificate chain. A depth of 0 means only the leaf certificate is checked.<br><br><b>-showcerts</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays the entire server certificate chain received during the handshake, including intermediate CAs.<br><br><b>-debug</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Provides verbose debugging output, showing detailed information about the SSL/TLS handshake process.<br><br><b>-state</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Prints the SSL/TLS handshake state as it progresses.<br><br><b>-crlf</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Translates CR to CRLF for input, useful when interacting with protocols that expect CRLF line endings.<br><br><b>-quiet</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Suppresses non-essential output, showing only the handshake results and connection info.<br><br><b>-servername <I>name</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the hostname for Server Name Indication (SNI), allowing the client to request a specific certificate from servers hosting multiple domains.<br><br><b>-alpn <I>protocols</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies a comma-separated list of Application-Layer Protocol Negotiation (ALPN) protocols to offer the server (e.g., 'h2,http/1.1').<br><br><b>-sess_out <I>file</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Writes the negotiated session data to a file for later resumption.<br><br><b>-sess_in <I>file</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Reads session data from a file to attempt session resumption.<br><br><b>-reconnect</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Attempts to reconnect to the server after the initial handshake, useful for testing session resumption.<br><br><b>-starttls <I>protocol</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Initiates a plain text connection and then upgrades it to SSL/TLS using the specified protocol (e.g., 'smtp', 'ftp', 'pop3', 'imap', 'xmpp', 'ldap').<br><br><b>-msg</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Shows all SSL/TLS messages that are sent and received.<br><br><b>-cipher <I>list</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies a list of acceptable OpenSSL ciphers for SSLv3/TLSv1.0/TLSv1.1/TLSv1.2 protocols.<br><br><b>-cipher_suites <I>list</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies a list of acceptable TLSv1.3 cipher suites. This option is distinct from <I>-cipher</I>.<br><br><b>-min_protocol <I>protocol</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets the minimum acceptable SSL/TLS protocol version (e.g., TLSv1.2).<br>Supported protocols: SSLv3, TLSv1, TLSv1.1, TLSv1.2, TLSv1.3.<br><br><b>-max_protocol <I>protocol</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets the maximum acceptable SSL/TLS protocol version (e.g., TLSv1.3).<br>Supported protocols: SSLv3, TLSv1, TLSv1.1, TLSv1.2, TLSv1.3.<br><br><b>-no_ssl3</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Disables SSLv3.<br><br><b>-no_tls1</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Disables TLSv1.0.<br><br><b>-no_tls1_1</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Disables TLSv1.1.<br><br><b>-no_tls1_2</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Disables TLSv1.2.<br><br><b>-no_tls1_3</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Disables TLSv1.3.<br><br>


title: DESCRIPTION
content:
The <I>openssl s_client</I> command is a versatile utility within the <I>OpenSSL</I> toolkit designed for establishing and analyzing SSL/TLS connections to remote hosts. It acts as a client, allowing users to interact with SSL/TLS servers, test server configurations, debug handshake issues, and inspect certificate chains. This tool is invaluable for administrators and developers to verify that a server's SSL/TLS setup is correct, to check if specific protocols or ciphers are supported, and to troubleshoot connectivity problems. It can display detailed information about the connection, including the negotiated protocol and cipher suite, the server's certificate, and the entire certificate chain received. Users can also provide client certificates for mutual authentication or load pre-existing session tickets for session resumption testing. Its interactive nature after a successful handshake makes it a powerful debugger for encrypted communication.


title: CAVEATS
content:
Using <I>openssl s_client</I> requires careful attention to its output, especially when diagnosing complex SSL/TLS issues.<br>Firewalls can block connections to specific ports, leading to connection timeouts or failures, even if the server is correctly configured.<br>Certificate verification failures are common and can be due to untrusted CAs, expired certificates, hostname mismatches, or incomplete certificate chains.<br>The command often requires full paths to certificate and key files, and incorrect permissions can lead to errors.<br>Protocols and cipher suites specified must be supported by both the client (OpenSSL version) and the server, otherwise handshakes will fail.<br>Some options, like <I>-cipher</I> and <I>-cipher_suites</I>, apply to different TLS versions and using the wrong one might not have the intended effect.


title: COMMON USE CASES
content:
<b><br>1. Verify Server Certificate and Chain:</b> Use <I>-showcerts</I> and <I>-verify</I> to inspect the server's certificate and ensure its chain is valid and trusted.<br><b>2. Test Specific Protocols/Ciphers:</b> Use <I>-min_protocol</I>, <I>-max_protocol</I>, <I>-cipher</I>, or <I>-cipher_suites</I> to check if a server supports particular security configurations.<br><b>3. Debug SNI Issues:</b> Use <I>-servername</I> to ensure that the correct certificate is presented when a server hosts multiple domains.<br><b>4. Check Mutual Authentication:</b> Use <I>-cert</I> and <I>-key</I> to test client certificate-based authentication.<br><b>5. Test STARTTLS:</b> Use <I>-starttls</I> with specific protocol names (e.g., smtp, imap) to test services that upgrade from plain text to SSL/TLS.


title: INTERACTIVE MODE
content:
After a successful SSL/TLS handshake, <I>openssl s_client</I> enters an interactive mode. Any input typed on the console is sent over the encrypted connection to the server, and any data received from the server is printed to the console. This allows for direct, secure interaction with the server, making it possible to send application-layer commands (like HTTP GET requests) and see the encrypted responses, which is highly valuable for debugging application-level protocols over TLS.


title: HISTORY
content:
The <I>s_client</I> utility is an integral part of the <I>OpenSSL</I> project, which originated in 1998 as a successor to the SSLeay library. Its development has closely tracked the evolution of the SSL/TLS protocols themselves, from the early SSLv2/v3 versions to the modern TLS 1.3. As new protocol features, cipher suites, and security enhancements (like SNI and ALPN) have been introduced, <I>s_client</I> has been updated to support them, making it an indispensable tool for anyone working with secure network communications. Its command-line interface has remained largely consistent, reflecting its long-standing utility and widespread adoption across Unix-like operating systems.


title: PARAMETERS
content:
<b>-accept <port></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the port number on which the server should listen for incoming connections. If not specified, it often defaults or is required.<br><br><b>-cert <file></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the file containing the server's certificate, typically a PEM-encoded X.509 certificate.<br><br><b>-key <file></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the file containing the server's private key. This key must correspond to the specified certificate.<br><br><b>-CAfile <file></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies a file containing trusted CA certificates. These are used to verify client certificates if client authentication is enabled.<br><br><b>-www</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Causes the server to respond to HTTP GET requests. Useful for testing web clients over SSL/TLS.<br><br><b>-HTTP</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Similar to <I>-www</I>, causing the server to respond to HTTP GET requests. A more explicit alias.<br><br><b>-cipher <spec></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the cipher list to be used by the server. The format of the cipher list is described in <b><I>ciphers</I>(1)</b>.<br><br><b>-ssl2, -ssl3, -tls1, -tls1_1, -tls1_2, -tls1_3</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Restricts the server to only use the specified SSL/TLS protocol version. For example, <I>-tls1_2</I> restricts to TLS 1.2.<br><br><b>-no_ssl2, -no_ssl3, etc.</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Disables the specified SSL/TLS protocol version.<br><br><b>-verify <depth></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Enables client certificate verification and sets the maximum verification depth.<br><br><b>-debug</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Prints extensive debugging information about the SSL/TLS handshake and data transfer.<br><br><b>-quiet</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Suppresses verbose output, showing only essential information.<br><br><b>-rand <file>[:<file>...]</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies files or EGD socket (file is the name of a file, or file is file:path for EGD). A random number generator is used for certain cryptographic operations.<br><br>


title: DESCRIPTION
content:
The <b><I>openssl s_server</I></b> command is a versatile diagnostic tool within the OpenSSL toolkit, designed to implement a generic SSL/TLS server for testing purposes. It allows developers and administrators to simulate an SSL/TLS server, enabling them to test and debug SSL/TLS clients, verify certificate configurations, and observe protocol handshakes. <br><br>This utility supports various SSL/TLS protocol versions, including SSLv2, SSLv3, TLSv1.0, TLSv1.1, TLSv1.2, and TLSv1.3, making it adaptable for a wide range of testing scenarios. Users can specify server certificates, private keys, trusted CA files, and desired cipher suites. It can also simulate common server behaviors, such as responding to HTTP GET requests, and provide detailed debugging output for troubleshooting connection issues. <br><br>While not intended for production use, <b><I>s_server</I></b> is invaluable during the development phase of SSL/TLS-enabled applications, helping to ensure secure and correctly configured communications.


title: CAVEATS
content:
The <b><I>s_server</I></b> utility is designed for testing and diagnostic purposes only. It is not built to be a robust, production-ready server and should not be deployed in live environments.<br><br>By default, it handles only one client connection at a time. To handle multiple connections, it would typically need to be run in a loop or integrated with a separate process management system (e.g., using <I>fork</I>).<br><br>Understanding the output, especially with <I>-debug</I> or <I>-msg</I>, requires familiarity with the SSL/TLS protocol details.


title: USAGE WITH S_CLIENT
content:
<b><I>s_server</I></b> is most commonly used in conjunction with <b><I>openssl s_client</I></b>. One instance acts as the server, and another as the client, allowing for end-to-end testing of SSL/TLS communication, certificate validation, and cipher negotiation.


title: CERTIFICATE AND KEY MANAGEMENT
content:
Before using <b><I>s_server</I></b>, you typically need to generate a server certificate and a private key. This can be done using other OpenSSL commands like <b><I>openssl req</I></b> and <b><I>openssl rsa</I></b>.


title: DEBUGGING HANDSHAKES
content:
The <I>-debug</I> and <I>-msg</I> options are crucial for understanding the SSL/TLS handshake process, identifying negotiation failures, and debugging certificate chain issues.


title: HISTORY
content:
The <b><I>s_server</I></b> command has been an integral part of the OpenSSL toolkit for many years, evolving alongside the SSL/TLS protocols themselves. Its development has mirrored the progression from early SSL versions (SSLv2, SSLv3) to the more secure and modern TLS standards (TLSv1.0, 1.1, 1.2, 1.3). It consistently receives updates to support new features, protocol enhancements, and security fixes implemented in the underlying OpenSSL library. Its primary role has always been to provide a flexible and reliable testing environment for developers working with secure network communications.


title: SEE ALSO
content:
<b><I>openssl</I>(1)</b>, <b><I>openssl s_client</I>(1)</b>, <b><I>openssl x509</I>(1)</b>, <b><I>openssl req</I>(1)</b>, <b><I>openssl ciphers</I>(1)</b>


title: PARAMETERS
content:
<b><b>-connect</b> <i>host</i>:<i>port</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the target host and port to connect to. This is typically the first argument after options.<br><br><b><b>-time</b> <i>seconds</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the duration, in seconds, for which the test should run. The default is 30 seconds.<br><br><b><b>-new</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Forces a new SSL/TLS handshake for each connection established. This measures the cost of initial handshakes.<br><br><b><b>-reuse</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;After the first full handshake, subsequent connections attempt to reuse the SSL session ID. This measures the cost of session resumption.<br><br><b><b>-bytes</b> <i>num</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the number of bytes to send and receive over the SSL/TLS connection after the handshake is complete. Useful for measuring data transfer performance.<br><br><b><b>-ssl2</b> | <b>-ssl3</b> | <b>-tls1_2</b> | <b>-tls1_3</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Forces the use of a specific SSL/TLS protocol version for the connection.<br><br><b><b>-cipher</b> <i>string</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the cipher suite or list of cipher suites to be used for the connection.<br><br><b><b>-cert</b> <i>file</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the client certificate file in PEM format for client authentication.<br><br><b><b>-key</b> <i>file</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the client private key file in PEM format corresponding to the certificate.<br><br><b><b>-verify</b> <i>level</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets the server certificate verification level. A value of 1 enables verification.<br><br><b><b>-CAfile</b> <i>file</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies a file containing trusted CA certificates in PEM format for server certificate verification.<br><br><b><b>-CApath</b> <i>directory</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies a directory containing trusted CA certificates in PEM format for server certificate verification.<br><br><b><b>-mr</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Outputs results per connection rather than accumulated statistics.<br><br><b><b>-www</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;After the SSL/TLS handshake, sends a simple HTTP GET request to the server and prints the response. Implies <b>-bytes</b>.<br><br>


title: DESCRIPTION
content:
The <b>s_time</b> utility is a command-line tool within the OpenSSL project designed to benchmark the performance of SSL/TLS handshakes and optional data transfer. It connects to a specified server, performs an SSL/TLS handshake, and can optionally send and receive data. The primary goal is to measure the rate at which a client can establish secure connections and transfer data over them. It reports various metrics such as the number of connections established, the total bytes transferred, and the real, user, and system times taken for the operations. This tool is invaluable for administrators and developers to assess the cryptographic overhead of their services, compare the performance of different cipher suites or protocol versions, and identify potential bottlenecks in their SSL/TLS configurations. It can be used for both new handshakes and session resumption scenarios.


title: CAVEATS
content:
Results obtained from <b>s_time</b> can be influenced by various factors beyond the cryptographic operations themselves, including network latency, server load, client machine specifications, and operating system overhead. It measures the client-side perspective of performance and might not fully represent server-side capacity under high concurrency. It is generally recommended to run such benchmarks on dedicated test environments with stable network conditions to get reliable and comparable results. This tool is primarily for benchmarking the SSL/TLS stack, not for general HTTP/application performance testing.


title: USAGE SCENARIOS
content:
<b>s_time</b> is commonly used for:<br><i>1. Benchmarking the performance impact of different SSL/TLS protocol versions (e.g., TLS 1.2 vs. TLS 1.3).</i><br><i>2. Comparing the efficiency of various cipher suites.</i><br><i>3. Assessing the overhead of client certificate authentication.</i><br><i>4. Measuring the benefit of SSL/TLS session resumption on handshake performance.</i><br><i>5. Quickly testing the responsiveness of an SSL/TLS enabled service from a client perspective.</i>


title: INTERPRETING RESULTS
content:
The output of <b>s_time</b> typically includes:<br><b>connections</b>: The total number of successful SSL/TLS handshakes completed.<br><b>bytes data read</b>: Total bytes of application data received (if <b>-bytes</b> or <b>-www</b> is used).<br><b>bytes data written</b>: Total bytes of application data sent (if <b>-bytes</b> or <b>-www</b> is used).<br><b>real time</b>: The wall-clock time elapsed during the test.<br><b>user time</b>: CPU time spent in user mode.<br><b>sys time</b>: CPU time spent in kernel mode.<br><b>connections per second</b>: A key metric indicating the rate of handshakes.<br><b>bytes per second</b>: A key metric indicating the data transfer rate.<br><br>High <i>connections per second</i> indicate efficient handshake establishment, while high <i>bytes per second</i> indicate good data throughput after the handshake. Comparing <i>real</i>, <i>user</i>, and <i>sys</i> times can help identify where the processing time is spent.


title: HISTORY
content:
The <b>s_time</b> utility is an integral part of the OpenSSL command-line toolkit, which originated from the SSLeay project in 1995. While specific version numbers for the introduction or major overhauls of <b>s_time</b> itself are not always explicitly documented in general release notes, its functionality has evolved alongside the OpenSSL library, incorporating support for new TLS versions (like TLS 1.2 and TLS 1.3) and cryptographic algorithms. It has consistently served as a fundamental tool for benchmarking the cryptographic performance of SSL/TLS implementations within the OpenSSL ecosystem.


title: PARAMETERS
content:
<b>-a</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Print all command names, even those that haven't been executed.<br><br><b>-b</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Print average statistics (CPU time, I/O) for commands, along with other data.<br><br><b>-D</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sort output by total disk I/O operations (blocks transferred).<br><br><b>-k</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Print CPU usage in <i>kcore-minutes</i>, a measure of memory * time.<br><br><b>-l</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Separate statistics for commands executed by `fork`ed processes (e.g., shell commands).<br><br><b>-m</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Print statistics for each user, including the total for all commands executed by that user.<br><br><b>-n</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sort output by the number of calls (executions) of each command.<br><br><b>-r</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Reverse the sorting order of the output.<br><br><b>-s</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Print a system-wide summary of accounting data, rather than individual command statistics.<br><br><b>-t</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Print the total number of characters transferred by processes.<br><br><b>-u</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Equivalent to <i>-m</i>; prints statistics for each user.<br><br><b>-v</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Verbose output; prints system usage (CPU time, I/O) by command.<br><br><b>[<i>files</i>]</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specify one or more alternative accounting files to read instead of the default.<br><br>


title: DESCRIPTION
content:
The <i>sa</i> command reads and summarizes information from the system's process accounting file, typically <i>/var/log/account/pacct</i> or <i>/var/account/pacct</i>. This file contains records of processes that have completed, including their CPU usage, I/O operations, memory consumption, and execution duration.<br><br><i>sa</i> is a crucial tool for system administrators to monitor resource consumption, identify heavily used commands or users, and analyze historical system activity. It can present data aggregated by command, per user, or provide a system-wide summary. The data collected by the kernel (when process accounting is enabled via <i>accton</i>) allows <i>sa</i> to provide insights into system workload patterns and aid in performance tuning and auditing.


title: CAVEATS
content:
Process accounting must be actively enabled on the system (typically via the <i>accton</i> command) for <i>sa</i> to collect and display data. If accounting is not enabled or the accounting file is empty, <i>sa</i> will report no data. The accounting file can grow very large and requires proper log rotation to prevent disk space exhaustion.


title: DATA SOURCE
content:
<i>sa</i> primarily reads its data from the system's process accounting file, which by default is often <i>/var/log/account/pacct</i> or <i>/var/account/pacct</i>. This binary file is populated by the kernel when process accounting is enabled.


title: ENABLING ACCOUNTING
content:
To collect data for <i>sa</i>, process accounting must be enabled. This is typically done by running <i>sudo accton /var/log/account/pacct</i> (or your chosen accounting file path). Without accounting enabled, <i>sa</i> will report no data.


title: HISTORY
content:
The <i>sa</i> command, along with the underlying process accounting system, has been a fundamental component of Unix-like operating systems since their early versions. Its core purpose of tracking and summarizing process resource usage for billing and system management has remained consistent over decades. While specific implementations and default file paths may vary slightly across different Linux distributions, <i>sa</i> is universally recognized as a standard utility for system monitoring and auditing, typically found within the <i>psacct</i> or <i>acct</i> packages.


title: PARAMETERS
content:
<b><b>-S</b> {<i>keyword</i>[,...]|<b>ALL</b>}</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specify the metrics to collect. Keywords include <b>CPU</b>, <b>DISK</b>, <b>IPV6</b>, <b>MEM</b>, <b>NET</b>, <b>POWER</b>, <b>PRES</b>, <b>SCSI</b>, <b>SNMP</b>, <b>USB</b>, or <b>ALL</b> for all available statistics. Multiple keywords can be comma-separated.<br><br><b><b>-U</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Do not update the current daily activity file. This option is primarily useful when <b>sa1</b> is invoked manually from a shell prompt for debugging or one-off collection purposes.<br><br><b><b>-V</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Display version number and exit.<br><br><b><i>interval</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;The time interval (in seconds) between two samples. If omitted, <b>sa1</b> collects a single sample. When used in <b>cron</b> jobs, this typically aligns with the <b>cron</b> interval.<br><br><b><i>count</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;The number of samples to collect. If omitted, <b>sa1</b> collects samples indefinitely (when <i>interval</i> is specified) or just one (when <i>interval</i> is also omitted).<br><br>


title: DESCRIPTION
content:
The <b>sa1</b> command is an essential component of the <b>sysstat</b> package, designed for collecting and saving daily system activity data. It acts as a data gatherer, typically invoked periodically by a <b>cron</b> job (e.g., every 10 minutes) to record various system metrics. These metrics include CPU utilization, memory usage, I/O activity, network statistics, and much more.<br><br><b>sa1</b> writes the collected data in a compact, binary format to a daily activity file, usually located in <I>/var/log/sysstat/</I>. The filename typically follows the pattern <I>saDD</I>, where <I>DD</I> represents the day of the month. This binary data serves as the source for the <b>sar</b> (System Activity Report) command, which can then display historical system performance information in a human-readable format. By continuously collecting data, <b>sa1</b> enables system administrators to analyze trends, identify performance bottlenecks, and troubleshoot issues over time. It's a foundational tool for proactive system monitoring.


title: CAVEATS
content:
<b>sa1</b> generates binary data files that are not human-readable directly; they must be parsed and displayed by the <b>sar</b> command. It relies on being regularly invoked, typically by a <b>cron</b> job, to maintain continuous system activity records. Disk space usage for historical data can accumulate over time if old <I>saDD</I> files are not regularly purged, which is usually handled by <b>sa2</b> or similar scripts. The default collection interval and scope are often configured in the <b>sysstat</b> package's configuration files (e.g., <I>/etc/default/sysstat</I> or <I>/etc/sysconfig/sysstat</I>).


title: CONFIGURATION FILES
content:
The behavior of <b>sa1</b> and the <b>sysstat</b> package is often controlled by configuration files such as <I>/etc/default/sysstat</I> or <I>/etc/sysconfig/sysstat</I> (depending on the Linux distribution). These files typically define variables like <b>HISTORY</b> (number of days to keep data), <b>COLLECT_INTERVAL</b> (default interval for <b>sa1</b>), and <b>SA_DIR</b> (directory for data files, usually <I>/var/log/sysstat/</I>).


title: DATA FILE LOCATION
content:
Collected data is stored in binary files, typically in <I>/var/log/sysstat/</I>. Filenames follow the pattern <I>saDD</I>, where <I>DD</I> is the day of the month (e.g., <I>sa01</I> for the first day, <I>sa15</I> for the fifteenth). These files are then read by <b>sar</b> to generate human-readable reports.


title: HISTORY
content:
<b>sa1</b> is an integral part of the <b>sysstat</b> utility suite, which has been a staple in Linux and Unix-like operating systems for performance monitoring for many years. Developed and maintained by Sebastien Godard, <b>sysstat</b> provides a comprehensive set of tools for system activity reporting. <b>sa1</b>'s role as the primary data collector has remained consistent, facilitating the long-term analysis of system performance trends. Its reliance on <b>cron</b> for periodic execution reflects a robust and automated approach to system data gathering, a design philosophy that has persisted since its early development.


title: PARAMETERS
content:
<b><b>-A</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays all available activities for the day, equivalent to specifying all report options.<br><br><b><b>-u</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Reports CPU utilization statistics, including user, nice, system, iowait, steal, and idle percentages.<br><br><b><b>-r</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Reports memory utilization statistics, including free, used, buffered, cached memory, and swap space usage.<br><br><b><b>-b</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Reports I/O and transfer rate statistics for block devices, including total and average transfer rates.<br><br><b><b>-d</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Reports individual block device I/O statistics, showing per-device activity.<br><br><b><b>-n DEV</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Reports network statistics for network interfaces (e.g., Rx/Tx packets, errors, collisions). Other network keywords like <I>EDEV</I>, <I>NFS</I>, <I>NFSD</I>, <I>SOCK</I>, <I>IP</I>, <I>EIP</I>, <I>ICMP</I>, <I>EICMP</I>, <I>TCP</I>, <I>ETCP</I>, <I>UDP</I>, <I>SOCK6</I>, <I>IP6</I>, <I>EIP6</I>, <I>ICMP6</I>, <I>EICMP6</I>, <I>UDP6</I>, <I>ALL</I> can be used.<br><br><b><b>-s HH:MM:SS</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets the starting time of the report. The default is 00:00:00 (midnight).<br><br><b><b>-e HH:MM:SS</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets the ending time of the report. The default is 23:59:59 (end of day).<br><br><b><b>-i interval</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets the interval (in seconds) between each sample displayed in the report. This option affects how many samples are displayed, not how often data is collected.<br><br><b><b>DD</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the day of the month (1-31) for which to display the report. If omitted, the current day is assumed, and <I>sa2</I> automatically selects the corresponding <I>/var/log/sa/saDD</I> file.<br><br>


title: DESCRIPTION
content:
<i>sa2</i> is a command-line utility used to display comprehensive daily system activity reports. It acts as a wrapper or a convenience script around the <I>sar</I>(1) command, specifically configured to read data collected by the <I>sadc</I> daemon for the current or a specified day. The data is typically stored in binary files like <I>/var/log/sa/saDD</I>, where <I>DD</I> represents the day of the month.<br><br>Its primary purpose is to simplify the retrieval and presentation of historical system performance metrics without needing to manually specify the data file. <I>sa2</I> can show various system statistics, including CPU utilization, memory usage, I/O activity, network statistics, and more, aggregated over a 24-hour period. This makes it an invaluable tool for system administrators and performance analysts to review daily trends, identify potential bottlenecks, and diagnose intermittent issues.


title: CAVEATS
content:
<i>sa2</i> relies on the <I>sysstat</I> package being installed and properly configured, specifically that the <I>sadc</I> data collector runs periodically (e.g., via cron) to generate the daily activity files in <I>/var/log/sa/</I>. If these files are not present or are incomplete, <I>sa2</I> will display no data or incomplete reports.<br><br>The exact implementation and availability of the <I>sa2</I> command may vary between Linux distributions. Some distributions may not provide <I>sa2</I> as a direct command, instead expecting users to invoke <I>sar</I> directly with the appropriate <I>-f</I> option for daily files.


title: <B>DATA SOURCE</B>
content:
<i>sa2</i> reads its data from daily activity files, typically named <I>/var/log/sa/saDD</I> (where <I>DD</I> is the day of the month), which are generated by the <I>sadc</I> data collector. These binary files contain snapshots of system activity taken at regular intervals, usually by a cron job running <I>sa1</I>.


title: <B>CONVENIENCE WRAPPER</B>
content:
While the same information can be obtained directly using the <I>sar</I> command with the <I>-f</I> option (e.g., <I>sar -A -f /var/log/sa/sa25</I>), <I>sa2</I> simplifies this process by automatically inferring the data file based on the current date or a specified day of the month, making it quicker and easier to review daily performance logs. Options passed to <I>sa2</I> are generally passed directly to the underlying <I>sar</I> command.


title: HISTORY
content:
The <I>sa2</I> command is an integral part of the <I>sysstat</I> utilities, a comprehensive collection of performance monitoring tools for Linux. The <I>sysstat</I> package was developed by Sébastien Godard. <I>sa2</I> (along with <I>sa1</I>) was introduced to simplify the automation and viewing of daily system activity reports, building upon the core functionality of <I>sar</I> and <I>sadc</I>. Its design facilitates easy access to historical performance data without requiring users to remember the specific file paths or complex <I>sar</I> syntax for daily reports.


title: PARAMETERS
content:
<b><b>-S</b> &lt;time&gt;<i>, --starttime=&lt;time&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Select jobs or steps that started or ended after the specified time. Time formats include YYYY-MM-DD[THH:MM[:SS]] or relative times like 'now', 'yesterday', or '-1hour'.<br><br><b><b>-E</b> &lt;time&gt;<i>, --endtime=&lt;time&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Select jobs or steps that started or ended before the specified time.<br><br><b><b>-j</b> &lt;job_list&gt;<i>, --jobs=&lt;job_list&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Display information for a comma-separated list of specific job IDs or job ID ranges.<br><br><b><b>-u</b> &lt;user_list&gt;<i>, --users=&lt;user_list&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Display information for a comma-separated list of user names or IDs.<br><br><b><b>-s</b> &lt;state_list&gt;<i>, --state=&lt;state_list&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Display jobs or steps matching the specified job states (e.g., COMPLETED, FAILED, RUNNING).<br><br><b><b>-o</b> &lt;format&gt;<i>, --format=&lt;format&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specify a comma-separated list of fields to display in the output (e.g., JobID,JobName,State,CPUTime).<br><br><b><b>-D</b><i>, --show-steps</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Display individual job steps in addition to the overall job information.<br><br><b><b>-X</b><i>, --no-steps</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Only display job information, suppressing the display of individual job steps.<br><br><b><b>-l</b><i>, --long</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Display more fields than the default output format.<br><br><b><b>-P</b><i>, --parsable</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Output in a machine-readable format, typically using a '|' delimiter.<br><br><b><b>-a</b><i>, --allusers</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Display accounting records for all users (requires administrative privileges).<br><br><b><b>-M</b> &lt;cluster_list&gt;<i>, --clusters=&lt;cluster_list&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specify a comma-separated list of cluster names to query.<br><br>


title: DESCRIPTION
content:
<b>sacct</b> is a command-line utility within the Slurm Workload Manager suite. Its primary function is to query and display historical accounting information for jobs and job steps that have completed, failed, or been canceled. Unlike <b>squeue</b>, which shows active jobs, <b>sacct</b> delves into the past, retrieving data from the Slurm accounting database (typically managed by <b>slurmdbd</b>). Users can filter results by various criteria such as job ID, user, time range, job state, and cluster. It provides a comprehensive view of resource utilization (CPU, memory, GPU), exit codes, submission and completion times, and other crucial metrics, making it invaluable for auditing, performance analysis, and resource management within a Slurm-managed HPC environment. The command supports flexible output formatting, allowing users to customize the displayed fields to suit specific analytical needs.


title: CAVEATS
content:
<b>sacct</b> relies on Slurm accounting (<b>slurmdbd</b>) being configured and running to store historical data. Data retention policies, set by administrators, dictate how long job records are kept, meaning older data might not be available. Queries over very large datasets or long time ranges can be slow. Users typically only have permissions to view their own job records unless granted administrative privileges.


title: COMMON OUTPUT FIELDS AND USAGE EXAMPLES
content:
When using the <b>-o</b><i>, --format</i> option, <b>sacct</b> allows specifying a wide range of fields to display. Common fields include <i>JobID</i>, <i>JobName</i>, <i>State</i>, <i>ExitCode</i>, <i>User</i>, <i>Start</i>, <i>End</i>, <i>ElapsedTime</i>, <i>CPUTime</i>, <i>MaxRSS</i> (maximum resident set size), <i>AllocNodes</i>, and <i>AllocCPUs</i>.<br><br>For example, to display the Job ID, Job Name, State, Exit Code, CPU Time, and Max RSS for a specific job:<br><code>sacct -j 12345 -o JobID,JobName,State,ExitCode,CPUTime,MaxRSS</code><br><br>To see all jobs for a user 'jdoe' that completed yesterday:<br><code>sacct -u jdoe -s COMPLETED -S yesterday</code>


title: HISTORY
content:
Slurm (Simple Linux Utility for Resource Management) was developed by Lawrence Livermore National Laboratory. <b>sacct</b> is an integral part of its accounting system, introduced to provide detailed historical job data which <b>squeue</b> doesn't cover. Its functionality has evolved alongside Slurm itself, improving query capabilities, performance, and output customization, becoming a crucial tool for HPC administrators and users for post-job analysis and chargeback.


title: SYNOPSIS
content:
<b>sacctmgr</b> [<I>GLOBAL_OPTIONS</I>] <I>COMMAND</I> [<I>COMMAND_OPTIONS</I>] [<I>ARGUMENTS</I>]<br><br>Common COMMANDs:<br>&nbsp;&nbsp;<b>add</b> <I>OBJECT</I> [<I>PARAMETERS</I>]<br>&nbsp;&nbsp;<b>modify</b> <I>OBJECT</I> [<I>PARAMETERS</I>]<br>&nbsp;&nbsp;<b>delete</b> <I>OBJECT</I> [<I>PARAMETERS</I>]<br>&nbsp;&nbsp;<b>show</b> <I>OBJECT</I> [<I>PARAMETERS</I>]<br>&nbsp;&nbsp;<b>list</b> <I>OBJECT</I> [<I>PARAMETERS</I>]<br><br>Common OBJECTs:<br>&nbsp;&nbsp;<b>account</b> | <b>user</b> | <b>association</b> | <b>cluster</b> | <b>qos</b> | <b>coordinators</b><br><br>Example Usage:<br>&nbsp;&nbsp;<i>sacctmgr add account new_department Description="Account for R&D"</i><br>&nbsp;&nbsp;<i>sacctmgr modify user jdoe DefaultAccount=new_department</i><br>&nbsp;&nbsp;<i>sacctmgr show association user=jdoe format=account,user,cluster,partition</i>


title: PARAMETERS
content:
<b><b>--clusters=&lt;string&gt;</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the clusters to operate on. Multiple cluster names can be comma-separated.<br><br><b><b>--federation</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Operates on the entire federation, if Slurm federation is configured.<br><br><b><b>--immediate</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Commits changes to the database immediately. This is often the default behavior for 'add', 'modify', and 'delete' commands.<br><br><b><b>--parsable</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Outputs results in a machine-readable format with fields separated by a vertical bar ('|'). Useful for scripting.<br><br><b><b>--parsable2</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Outputs results in an enhanced machine-readable format, similar to <b>--parsable</b> but with more details and often better suited for complex parsing.<br><br><b><b>--quiet</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Suppresses informational messages, showing only errors or requested output.<br><br><b><b>--readonly</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Prevents any modifications to the Slurm database, useful for testing commands or viewing configurations safely.<br><br><b><b>--help</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays a brief help message for the <b>sacctmgr</b> command or a specific subcommand.<br><br><b><b>--version</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays the version of <b>sacctmgr</b> being used.<br><br><b><b>--name=&lt;string&gt;</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Used with <b>show</b> commands to filter results by name, e.g., an account name or user name.<br><br><b><b>--level=&lt;int&gt;</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the depth level for 'show tree' commands, controlling how many levels of hierarchy are displayed.<br><br><b><b>--noheader</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Suppresses the header line in the output of 'show' commands, useful for scripting.<br><br><b><b>--port=&lt;port&gt;</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the port number to connect to the <i>slurmdbd</i> daemon.<br><br><b><b>--local</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Ensures that <b>sacctmgr</b> connects only to the local <i>slurmdbd</i> daemon, avoiding any potential remote connections configured.<br><br>


title: DESCRIPTION
content:
<b>sacctmgr</b> is a powerful administrative command-line utility for managing the Slurm Workload Manager's accounting database. It enables system administrators to define and control resource allocation policies by manipulating <i>accounts</i>, <i>users</i>, <i>associations</i> (linking users to accounts on specific clusters), <i>clusters</i>, and <i>Quality of Service (QOS)</i> definitions. This tool is essential for setting up fairshare policies, enforcing usage limits, and organizing the hierarchical structure of resource access within a Slurm cluster or federation of clusters.<br><br>Through <b>sacctmgr</b>, administrators can add new accounts, modify existing user permissions and limits, delete obsolete entries, and review the current configuration of the Slurm database. It interacts directly with the <i>Slurm Database Daemon (slurmdbd)</i>, ensuring that all changes are immediately reflected in the system's resource management logic. Its comprehensive set of commands and options provides granular control over who can access what resources and under what conditions, making it a cornerstone for effective Slurm cluster management.


title: CAVEATS
content:
Using <b>sacctmgr</b> requires administrative privileges, typically root or the SlurmUser. Because it directly modifies the Slurm accounting database, extreme caution must be exercised; incorrect commands can disrupt resource allocation, job scheduling, or user access across the cluster. It's crucial to understand Slurm's account hierarchy, QOS definitions, and fairshare principles before making significant changes. Always verify your commands, especially when performing 'delete' operations. While changes are generally immediate, it's wise to double-check their effect using 'show' commands.


title: UNDERSTANDING SLURM ACCOUNTING HIERARCHY
content:
Slurm uses a hierarchical accounting system to organize users and resource consumption. At the top are <b>accounts</b>, which can represent departments, projects, or groups. Accounts can be nested, forming a tree structure (e.g., 'department_A' -> 'project_X'). <b>Users</b> are associated with one or more accounts, and their resource usage is charged against these associations. This hierarchy, managed largely through <b>sacctmgr</b>, is fundamental to implementing fairshare scheduling and managing resource limits effectively across an organization.


title: INTEGRATION WITH QUALITY OF SERVICE (QOS)
content:
Quality of Service (<b>QOS</b>) objects, managed by <b>sacctmgr</b>, define various job submission and execution parameters such as maximum job run time, maximum number of jobs, priority, and preemption rules. QOS can be assigned to accounts, users, or associations, providing a flexible mechanism to enforce resource policies. Administrators use <b>sacctmgr</b> to create new QOS definitions, modify existing ones, and assign them to specific entities, profoundly influencing how jobs from different groups or users are prioritized and constrained.


title: HISTORY
content:
<b>sacctmgr</b> is an integral part of the Slurm Workload Manager, a highly scalable and fault-tolerant cluster management and job scheduling system for large and small Linux clusters. Slurm was originally developed by Lawrence Livermore National Laboratory (LLNL) and released as open-source in 2002. As Slurm evolved to manage complex resource allocation and accounting, the need for a dedicated administrative tool for its database became apparent. <b>sacctmgr</b> was introduced to provide a robust, command-line interface for managing the hierarchical accounting structures, users, clusters, and Quality of Service (QOS) policies stored within the <i>slurmdbd</i> database. Its development has paralleled Slurm's growth, incorporating features like federation support and more granular control over resource limits, making it a cornerstone for Slurm administrators.


title: SEE ALSO
content:
sacct(1), sbatch(1), srun(1), salloc(1), squeue(1), sinfo(1), scontrol(1), slurm.conf(5), slurmdbd(8)


title: PARAMETERS
content:
<b><i>interval</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;The amount of time in seconds between two consecutive data collections.<br><br><b><i>count</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;The number of data collections to be made. If omitted, data is collected indefinitely until termination.<br><br><b><i>output_file</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;The path to the file where the collected binary system activity data will be saved. If omitted, data is written to standard output.<br><br><b>-F</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Display the file header and the data collected from the input file in a human-readable format. This option is useful for debugging <b>sadc</b> data files.<br><br><b>-L</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Store statistics in a local file. This option is typically used by the <b>sa1</b> script to specify a local output file.<br><br><b>-S {<i>keyword</i>[,...]|ALL}</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies which system activity units are to be saved. For example, 'CPU,DISK' to save only CPU and disk statistics. Use 'ALL' to save all available units.<br><br><b>-C {<i>keyword</i>[,...]|ALL}</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies which system activity units are to be read from the input file. This is used when processing an existing <b>sadc</b> file for analysis or manipulation, similar to <b>sar</b>'s data selection.<br><br>


title: DESCRIPTION
content:
<b>sadc</b> (System Activity Data Collector) is a fundamental component of the <i>sysstat</i> package, designed to gather comprehensive system activity data. It collects various performance metrics such as CPU utilization, memory usage, I/O statistics, network activity, process information, and more. Unlike other <i>sysstat</i> tools like <b>sar</b> or <b>iostat</b> that display real-time or historical data, <b>sadc</b>'s primary role is to act as a backend data collector. It writes this raw, binary data to a specified file, typically located in <i>/var/log/sa/</i>. This binary format is highly efficient for storage. The collected data can then be processed and analyzed by other tools, most notably <b>sar</b>, which can read these files and present the information in a human-readable format, either for historical analysis or real-time monitoring (when <b>sar</b> acts as both collector and reporter). <b>sadc</b> is usually invoked automatically by the <b>sa1</b> script, which is often configured to run periodically via <i>cron</i> jobs, ensuring continuous system monitoring without manual intervention.


title: CAVEATS
content:
The output file generated by <b>sadc</b> is in a binary format and is not directly human-readable; it requires tools like <b>sar</b> to parse and display its contents. <b>sadc</b> often requires root privileges to collect comprehensive system activity data. It is typically not invoked directly by users but rather by the <b>sa1</b> script as part of automated <i>cron</i> jobs for continuous system monitoring.


title: TYPICAL USAGE WITH <I>CRON</I>
content:
<b>sadc</b> is rarely run directly by users. Instead, it's usually invoked by the <b>sa1</b> script, which is part of the <i>sysstat</i> utilities. The <b>sa1</b> script itself is typically scheduled to run at regular intervals (e.g., every 10 minutes) via <i>cron</i>. This automated setup ensures continuous collection of system performance data without manual intervention, saving it to files in <i>/var/log/sa/</i> (e.g., <i>saDD</i> or <i>saYYYYMMDD</i>). These daily files form a historical record that can be analyzed later using <b>sar</b>.


title: HISTORY
content:
<b>sadc</b> is an integral part of the <i>sysstat</i> package, a suite of performance monitoring tools that have been a cornerstone of Linux system administration for many years. Its development has mirrored the evolution of Linux kernels, continuously adding support for new metrics and system architectures, making it a reliable and robust tool for historical performance analysis.


title: SYNOPSIS
content:
<b>sadf</b> [ <i>options</i> ] [ <i>&lt;interval&gt;</i> [ <i>&lt;count&gt;</i> ] ] [ <i>&lt;sarfile&gt;</i> ]<br><br><b>Common Options:</b><br> <b>sadf</b> <b>-C</b> [ <i>&lt;sarfile&gt;</i> ]<br> <b>sadf</b> <b>-j</b> [ <b>-H</b> ] [ <b>-P</b> <i>{ CPU | ALL }</i> ] [ <b>-s</b> <i>[ hh:mm:ss ]</i> ] [ <b>-e</b> <i>[ hh:mm:ss ]</i> ] [ <i>&lt;sarfile&gt;</i> ]<br> <b>sadf</b> <b>-x</b> [ <b>-H</b> ] [ <b>-P</b> <i>{ CPU | ALL }</i> ] [ <b>-s</b> <i>[ hh:mm:ss ]</i> ] [ <b>-e</b> <i>[ hh:mm:ss ]</i> ] [ <i>&lt;sarfile&gt;</i> ]


title: PARAMETERS
content:
<b><i>&lt;interval&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Time in seconds between samples to be reported. Used for real-time reporting if no <i>&lt;sarfile&gt;</i> is specified.<br><br><b><i>&lt;count&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Number of samples to be collected or reported. Used for real-time reporting if no <i>&lt;sarfile&gt;</i> is specified.<br><br><b><i>&lt;sarfile&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Path to the <i>sar</i> data file to process (e.g., <i>/var/log/sysstat/saDD</i> where DD is the day of the month). If omitted, <i>sadf</i> processes the current day's file.<br><br><b><b>-C</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Write <i>sar</i> data from multiple files in CSV format. This option is used when concatenating data from different <i>sar</i> data files.<br><br><b><b>-D</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Display <i>sar</i> data in a format readable by the <i>sar</i> command. This is the default output format when no other format options (like <b>-j</b>, <b>-x</b>) are specified.<br><br><b><b>-g</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Display <i>sar</i> data in SVG (Scalable Vector Graphics) format. This can be used for basic graphical representation of metrics.<br><br><b><b>-H</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Display only the header for CSV, XML, or JSON output. Useful for understanding the structure of the data without processing the entire file.<br><br><b><b>-j</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Display <i>sar</i> data in JSON format, making it easy to parse with scripting languages and integrate into web applications.<br><br><b><b>-L</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Display <i>sar</i> data in local time instead of Coordinated Universal Time (UTC) which is the default.<br><br><b><b>-P</b> <i>{ CPU | ALL }</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Report activity for a specific processor (e.g., <b>-P 0</b> for the first CPU) or for all processors (<b>-P ALL</b>).<br><br><b><b>-p</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Display <i>sar</i> data in a "pretty print" format, which is similar to <i>sar</i>'s traditional columnar output but can also be used to concatenate data from multiple files.<br><br><b><b>-s</b> <i>[ hh:mm:ss ]</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Set the starting time of the report. Data collected before this time will not be displayed.<br><br><b><b>-e</b> <i>[ hh:mm:ss ]</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Set the ending time of the report. Data collected after this time will not be displayed.<br><br><b><b>-t</b> <i>[ hh:mm:ss ]</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Set the time interval of the records displayed. This can be used to filter data based on the collection interval.<br><br><b><b>-T</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Display timestamps for each record, providing precise timing information alongside the metrics.<br><br><b><b>-x</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Display <i>sar</i> data in XML format, providing a structured and extensible way to represent the system activity data.<br><br><b><b>-V</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Print the version number of the <i>sysstat</i> utilities, which includes <i>sadf</i>.<br><br><b><b>-v</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Print the <i>sadf</i> version number.<br><br><b><b>-h</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Print a help message and exit.<br><br>


title: DESCRIPTION
content:
<i>sadf</i> (System Activity Data File) is a utility within the <b>sysstat</b> package used to read and display data collected by the <i>sar</i> command. Unlike <i>sar</i> which primarily displays data in a human-readable, columnar format, <i>sadf</i> offers options to export this system activity information into machine-parsable formats such as CSV (Comma Separated Values), XML, or JSON. This makes <i>sadf</i> invaluable for scripting, data analysis, integration with other tools, or long-term archiving of performance data. It can process real-time data or historical data stored in <i>sar</i> data files, allowing users to analyze system performance metrics like CPU utilization, memory usage, I/O activity, network statistics, and more, in a structured way.


title: CAVEATS
content:
<i>sadf</i>'s functionality is entirely dependent on the availability and integrity of <i>sar</i> data files. If <i>sar</i> is not configured to collect data, or if the data files are missing or corrupted, <i>sadf</i> will not be able to generate reports.<br>For large datasets, the XML, JSON, or CSV output can be very verbose, potentially consuming significant disk space or memory if not handled efficiently. External parsing tools are often required for effective analysis of these outputs.


title: OUTPUT FORMATS
content:
<i>sadf</i> supports several output formats, making it highly flexible for various use cases:<br> - <i>CSV (Comma Separated Values)</i>: Generated using options like <b>-C</b>, ideal for spreadsheet analysis and simple scripting.<br> - <i>XML</i>: Generated with the <b>-x</b> option, providing a structured data format suitable for parsing with XML parsers.<br> - <i>JSON</i>: Generated with the <b>-j</b> option, a lightweight, human-readable data format widely used in web applications and scripting for data exchange.<br> - <i>"Pretty Print"</i>: Generated with the <b>-p</b> option, which mimics <i>sar</i>'s traditional columnar output but can combine data from multiple files.<br> - <i>SVG (Scalable Vector Graphics)</i>: Generated with the <b>-g</b> option, useful for simple visualizations.<br>These diverse formats are crucial for enabling automated performance monitoring, data warehousing, and seamless integration with external visualization and analysis tools.


title: HISTORY
content:
<i>sadf</i> is an integral part of the <i>sysstat</i> package, which originated in the late 1990s as a set of tools for collecting and reporting Linux system activity. <i>sadf</i> specifically gained prominence with the increasing need for machine-readable output of performance data, evolving from simple text formats to support CSV, XML, and JSON. Its development has mirrored the growing complexity of Linux system performance analysis, facilitating automation, integration with monitoring systems, and advanced data analytics.


title: SYNOPSIS
content:
<b>safe</b> [<i>safe_options</i>] <i>command</i> [<i>command_options</i>] [-- <i>command_arguments</i>]


title: PARAMETERS
content:
<b><b>--dry-run</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Performs a simulated execution of the <i>command</i>, showing what actions would be taken without actually modifying the system. This is crucial for verifying the intended scope and impact of an operation.<br><br><b><b>--confirm</b>, <b>-i</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Prompts the user for confirmation before executing the <i>command</i>. For commands affecting multiple files, it may prompt for each file or group of files.<br><br><b><b>--backup</b>, <b>-b</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Before the <i>command</i> modifies any files, <i>safe</i> creates a timestamped or versioned backup of the original files. This allows for easy restoration in case of unintended consequences.<br><br><b><b>--undo-log</b>, <b>-u</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Logs all actions performed by the <i>command</i> in a structured format, enabling potential reversal of operations. This might involve recording moved files, permission changes, or deleted entries.<br><br><b><b>--chroot &lt;path&gt;</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Executes the wrapped <i>command</i> within a specified chroot environment, isolating its operations from the main file system and providing a sandbox for testing or sensitive tasks.<br><br><b><b>--user &lt;user&gt;</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Runs the <i>command</i> as the specified user, similar to <i>sudo -u</i> but managed by <i>safe</i>'s wrapper, ensuring permissions are appropriately handled within the safe context.<br><br><b><b>--group &lt;group&gt;</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Runs the <i>command</i> with the specified group permissions.<br><br>


title: DESCRIPTION
content:
The <i>safe</i> command is a conceptual Linux utility designed to act as a protective wrapper for other potentially destructive or irreversible operations. It aims to prevent accidental data loss or system misconfigurations by introducing a layer of interactive control and preventative measures. Ideal for critical system administration tasks, scripting, or exploratory work, <i>safe</i> allows users to preview actions, get confirmations, or automatically create backups before a command modifies the system. While not a standard pre-installed command in most Linux distributions, its functionality represents a collection of best practices and patterns often implemented through shell aliases, custom scripts, or specialized tools to enhance operational safety. Its primary goal is to provide a robust framework for cautious command execution, mitigating risks associated with powerful utilities like <i>rm</i>, <i>mv</i>, <i>chown</i>, or <i>chmod</i>.


title: CAVEATS
content:
The <i>safe</i> command, while providing significant protection, cannot guarantee absolute safety. Its effectiveness depends on the nature of the wrapped command; low-level system calls or direct hardware manipulation might bypass its protective layers. Automatic backups consume disk space, and comprehensive undo mechanisms can be complex to implement for all possible command effects. Users should still exercise caution and understand the implications of the underlying command.


title: BEST PRACTICES EMULATED
content:
<i>safe</i> encapsulates several vital system administration best practices: always test with dry-runs, confirm destructive actions, and maintain backups. It reduces the cognitive load of remembering specific flags for each command by providing a consistent safety interface.


title: CONCEPTUAL IMPLEMENTATION
content:
A real-world <i>safe</i> command could be implemented as a shell script, a Python wrapper, or a more sophisticated tool leveraging technologies like Linux namespaces (for sandboxing), FUSE (for virtual file systems that track changes), or even system call interception (e.g., via <i>LD_PRELOAD</i> for advanced dry-run capabilities).


title: HISTORY
content:
The concept of a 'safe' command originates from the fundamental need for risk management in Unix-like environments. While no single command named <i>safe</i> has been standardized across all Linux distributions, its principles are deeply embedded in system administration best practices. Historically, users have achieved similar safety by using aliases (e.g., <i>alias rm='rm -i'</i>), writing custom wrapper scripts, or relying on specific command options like <i>--backup</i> or <i>--interactive</i>. The idea of a unified <i>safe</i> command encapsulates these disparate safety mechanisms into a single, cohesive interface, representing an evolution towards more robust and user-friendly system management tools.


title: PARAMETERS
content:
<b>user</b><br>&nbsp;&nbsp;&nbsp;&nbsp;The username to query information for. If omitted, information about all logged-in local users might be displayed, depending on the specific implementation of <b>safe_finger</b>.<br><br><b>options</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specific options are highly dependent on the particular <b>safe_finger</b> implementation. Common <b>finger</b>-like options such as <b>-s</b> (short format) or <b>-m</b> (exact match) might be supported, but extensive options are unlikely given its security-focused nature. Typically, it defaults to the most secure and restricted output.<br><br>


title: DESCRIPTION
content:
The <b>safe_finger</b> command is typically a wrapper or a custom implementation designed to provide a more secure and restricted version of the traditional <b>finger</b> command. The standard <b>finger</b> command is often disabled on modern systems due to security concerns, as it can reveal sensitive user information such as login times, idle times, and <i>.plan</i> or <i>.project</i> files, potentially aiding attackers in reconnaissance. <b>safe_finger</b> aims to mitigate these risks by enforcing stricter access controls or limiting the amount of information disclosed. It might only allow querying local users, restrict output to basic user details (e.g., username, full name, terminal), or require specific permissions to execute. Its primary purpose is to allow system administrators to retain some user information lookup capability without exposing excessive data. It's not a standard Linux utility and is usually found in hardened environments or custom setups where controlled user information access is necessary.


title: CAVEATS
content:
The <b>safe_finger</b> command is not a standard Linux utility and its exact behavior, options, and output are entirely dependent on the specific implementation or wrapper script provided by a system administrator or distribution. It is typically designed to be a local-only tool or to restrict information disclosure significantly compared to the traditional <b>finger</b> command. Therefore, its capabilities and limitations will vary greatly. Relying on <b>safe_finger</b> for comprehensive user information is not advisable, as its primary goal is information restriction.


title: HISTORY
content:
The concept of <b>safe_finger</b> emerged as a direct response to the inherent security vulnerabilities of the original <b>finger</b> command and protocol. The <b>finger</b> service, introduced in the early days of ARPANET and common on Unix-like systems, was designed for convenient user information lookup. However, its broad disclosure of details like login times, idle status, home directories, and user-editable <i>.plan</i> and <i>.project</i> files became a significant information leakage risk as internet security concerns grew. Many organizations disabled <b>finger</b> entirely. <b>safe_finger</b>, therefore, isn't a single, standardized command but rather represents a class of custom wrappers or restricted implementations developed by system administrators to regain some controlled user information lookup capability while minimizing the attack surface presented by the traditional <b>finger</b> utility. Its development is decentralized, driven by specific security requirements.


title: SYNOPSIS
content:
<I>sail</I> <I>[command]</I> <I>[options]</I> <I>[arguments]</I><br><i>(Invoked via <I>vendor/bin/sail</I> or a shell alias)</i><br><br><I>php artisan sail</I> <I>[command]</I> <I>[options]</I> <I>[arguments]</I><br><i>(The most common invocation within a Laravel project)</i>


title: PARAMETERS
content:
<b>up</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Starts all defined Docker containers in the background. Options include <b>-d</b> for detached mode.<br><br><b>down</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Stops and removes all containers, networks, and volumes defined for the Sail environment. Options include <b>--rmi all</b> to remove images as well.<br><br><b>build</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Builds or rebuilds the Docker images for the services. Useful after making changes to the Dockerfile or context.<br><br><b>artisan</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Executes a Laravel Artisan command inside the PHP container. Example: <b>sail artisan migrate</b>.<br><br><b>composer</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Runs a Composer command inside the PHP container. Example: <b>sail composer require foo/bar</b>.<br><br><b>php</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Executes a PHP command or script inside the PHP container. Example: <b>sail php --version</b>.<br><br><b>npm / yarn</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Executes an npm or yarn command inside the Node.js container (if configured). Example: <b>sail npm run dev</b>.<br><br><b>test</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Runs PHPUnit tests inside the PHP container. Example: <b>sail test --filter PaymentTest</b>.<br><br><b>shell</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Opens a bash shell session inside the PHP container, allowing direct interaction with the environment.<br><br><b>logs</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays log output from the Sail services. Options include <b>-f</b> for follow mode.<br><br><b>stop</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Stops running Docker containers without removing them, preserving their state.<br><br>


title: DESCRIPTION
content:
Laravel Sail is a light-weight command-line interface (CLI) for interacting with Laravel's default Docker development environment. It provides a simple way to bootstrap and manage a local development stack including services like <b>PHP</b>, <b>Nginx</b>, <b>MySQL</b>, <b>Redis</b>, <b>Mailpit</b>, and more, all running within Docker containers.<br><br>The <I>sail</I> command abstracts away complex Docker commands, allowing developers to focus on writing code without deep Docker knowledge. It is typically installed via Composer within a Laravel project and commonly invoked as <I>php artisan sail</I> or through a shell alias. Sail ensures consistency across development environments by enabling execution of various application commands like <I>artisan</I>, <I>composer</I>, <I>npm</I>, <I>php</I>, and <I>test</I> directly within its Docker containers. It significantly streamlines the setup and maintenance of a robust Laravel development environment on Linux, macOS, and Windows (via WSL2).


title: CAVEATS
content:
Sail requires <b>Docker Desktop</b> (on macOS/Windows) or <b>Docker Engine</b> (on Linux) to be installed and running on the host machine. It is specifically designed for Laravel development and relies on the <I>docker-compose.yml</I> file generated or configured by Laravel. For optimal performance on Windows, it is highly recommended to use <b>WSL2 (Windows Subsystem for Linux 2)</b>.


title: INSTALLATION AND CONFIGURATION
content:
To use Sail, ensure you have Docker installed, then run <I>composer require laravel/sail --dev</I> in your Laravel project. Afterward, execute <I>php artisan sail:install</I> to publish the <I>docker-compose.yml</I> file. You can then configure services like MySQL, PostgreSQL, Redis, etc., by uncommenting them in the generated file.


title: HISTORY
content:
Laravel Sail was first introduced in <b>August 2020</b> as part of <b>Laravel 8</b>. Its primary goal was to simplify the Docker setup process for Laravel developers and provide a consistent, official development environment out-of-the-box. It rapidly gained adoption as the preferred local development solution for many Laravel projects, evolving with subsequent Laravel releases to support new features and services.


title: PARAMETERS
content:
<b><b>-A</b>, <b>--account</b>=<I>account</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Charge resources used by this job to the specified account.<br><br><b><b>-C</b>, <b>--constraint</b>=<I>list</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Request nodes with a specific feature (e.g., K80, V100).<br><br><b><b>-D</b>, <b>--dependency</b>=<I>type:job_id[:job_id...]</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Defer the allocation until the specified job(s) complete.<br><br><b><b>-G</b>, <b>--gpus</b>=<I>count</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Request a specific number of GPUs per node or total.<br><br><b><b>-J</b>, <b>--job-name</b>=<I>name</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specify a name for the job.<br><br><b><b>-L</b>, <b>--licenses</b>=<I>licenses</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Request a specific set of licenses.<br><br><b><b>-N</b>, <b>--nodes</b>=<I>min_nodes[-max_nodes]</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Request a specific number of nodes.<br><br><b><b>-n</b>, <b>--ntasks</b>=<I>number</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Request a specific number of tasks (processes).<br><br><b><b>-p</b>, <b>--partition</b>=<I>partition_name</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Request a specific partition.<br><br><b><b>-t</b>, <b>--time</b>=<I>time</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Set a time limit for the job (e.g., '1:00:00' for 1 hour).<br><br><b><b>--exclusive</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Allocate nodes exclusively for this job.<br><br><b><b>--mem</b>=<I>size</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specify maximum real memory per node (e.g., '10G', '500M').<br><br><b><b>--mem-per-cpu</b>=<I>size</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specify maximum real memory per allocated CPU (e.g., '100M').<br><br><b><b>--cpus-per-task</b>=<I>count</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Request 'count' number of CPUs per task.<br><br>


title: DESCRIPTION
content:
<i>salloc</i> is a Slurm command used to allocate resources for an interactive job on a cluster. Unlike <i>sbatch</i>, which submits a job script for batch execution, <i>salloc</i> initiates an interactive shell session on the first allocated node. This allows users to directly interact with the allocated resources, execute commands, debug code, and test applications in real-time. It's particularly useful for development, short-term testing, or when an immediate interactive environment is required. The allocation remains active until the user exits the shell or the requested time limit is reached. Resources are reserved for the exclusive use of the job during its allocation duration, even if the user is not actively executing commands within the shell.


title: CAVEATS
content:
<i>salloc</i> allocates resources but does not automatically execute commands across all allocated nodes or tasks. To run parallel tasks or commands on multiple nodes within an <i>salloc</i> session, you must use <i>srun</i>. It's crucial to exit the <i>salloc</i> shell (e.g., using 'exit' or Ctrl+D) when done to release resources; otherwise, the allocation will persist until its time limit is reached, potentially impacting fair share policies for other users.


title: HOW IT WORKS
content:
When you execute <i>salloc</i>, it requests resources from the Slurm scheduler based on your specified options (nodes, time, memory, etc.). Once the resources are available, Slurm allocates them, assigns a Job ID, and then spawns a shell (usually your default shell) on the first allocated compute node. Any commands you type in this shell will run on that node. To utilize the full allocation (e.g., run a parallel MPI job across multiple nodes), you typically invoke <i>srun</i> from within this interactive shell.


title: ENVIRONMENT VARIABLES
content:
Upon a successful <i>salloc</i> allocation, several Slurm-specific environment variables are set within the interactive shell, providing information about the job. Key variables include:<br><b>SLURM_JOB_ID</b>: The unique ID of the allocated job.<br><b>SLURM_NNODES</b>: The total number of nodes allocated.<br><b>SLURM_CPUS_ON_NODE</b>: Number of CPUs on the current node.<br><b>SLURM_NTASKS</b>: Total number of tasks requested for the job.


title: HISTORY
content:
<i>salloc</i> is an integral part of the Slurm Workload Manager, which originated in 2002. Slurm (Simple Linux Utility for Resource Management) was developed as a free, open-source job scheduler for Linux clusters. <i>salloc</i> was introduced early in Slurm's development to provide interactive resource allocation, addressing the need for immediate, on-demand access to cluster resources for debugging and development tasks, complementing the traditional batch processing model.


title: SYNOPSIS
content:
<b>salt</b> &lt;<i>target</i>&gt; &lt;<i>function</i>&gt; [<i>arguments</i>] [<i>options</i>]<br><br><i>Examples:</i><br><b>salt</b> '*' test.ping<br><b>salt</b> 'webservers' state.apply apache<br><b>salt</b> -G 'os:Ubuntu' cmd.run 'ls -l /etc/'


title: PARAMETERS
content:
<b>-t, --target-type</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Defines how the target expression is interpreted (e.g., <i>glob</i>, <i>grain</i>, <i>list</i>, <i>pcre</i>, <i>compound</i>).<br><br><b>-L, --list</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Target a list of minions provided as a comma-separated string.<br><br><b>-G, --grain</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Target minions based on specific grain values (e.g., <i>os:Ubuntu</i>).<br><br><b>-C, --compound</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Target minions using a compound match expression, combining different target types.<br><br><b>-E, --pcre</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Target minions using PCRE (Perl Compatible Regular Expression) on their IDs.<br><br><b>-a, --arg</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Pass positional arguments to the execution module function.<br><br><b>--timeout</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Set the maximum execution time in seconds for the command (default 5 seconds).<br><br><b>-J, --json</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Output the results in JSON format.<br><br><b>-v, --verbose</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Increase the verbosity of the output.<br><br><b>--state-output</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the format for state module output (e.g., <i>full</i>, <i>changes</i>, <i>terse</i>, <i>mixed</i>).<br><br><b>--async</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Execute the command asynchronously, returning a job ID immediately and running in the background.<br><br><b>--out, --output</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specify the output formatter for the results (e.g., <i>json</i>, <i>yaml</i>, <i>raw</i>, <i>highstate</i>).<br><br><b>--log-level</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Set the level of logging messages to display (e.g., <i>debug</i>, <i>info</i>, <i>warning</i>, <i>error</i>).<br><br>


title: DESCRIPTION
content:
<i>salt</i> is the primary command-line interface for <i>SaltStack</i>, an open-source, Python-based automation and configuration management system.<br><br>It allows users to issue commands to <i>Salt</i> minions (managed servers) from a <i>Salt</i> master. The command supports various targeting mechanisms to select specific minions or groups of minions. Key functionalities include remote execution (running arbitrary commands or modules), state management (applying desired configurations defined in <i>Salt</i> states), and orchestration (coordinating actions across multiple systems).<br><br><i>salt</i> leverages a fast, secure, and bidirectional communication layer for efficient operations at scale. It's widely used for server provisioning, software deployment, system maintenance, and infrastructure automation in data centers and cloud environments.


title: CAVEATS
content:
Using the <i>salt</i> command requires a running <i>Salt</i> master and minions connected to it, with their keys accepted.<br><br>Proper firewall configuration is necessary to allow communication between master and minions (default ports: 4505 and 4506 for master, 4506 for minion communication).<br><br>Incorrect targeting or function calls can lead to unintended changes across multiple systems. Always test commands in a safe environment first.<br><br>The power of remote execution implies significant security considerations; ensure master and minion security best practices are followed.


title: COMMON USAGE PATTERNS
content:
<b>Remote Execution:</b> Run an arbitrary command on targeted minions.<br><i>Example:</i> <code>salt '*' cmd.run 'uptime'</code><br><br><b>State Application:</b> Apply a defined configuration state.<br><i>Example:</i> <code>salt 'webservers' state.apply apache</code><br><br><b>Targeting Specific Minions:</b> Use various methods to select minions.<br><i>Example:</i> <code>salt -G 'os:CentOS' test.ping</code> (target by grain)<br><br><b>Module Functions:</b> Interact with Salt's execution modules.<br><i>Example:</i> <code>salt 'dbserver' pkg.install mysql-server</code>


title: HISTORY
content:
SaltStack was created by Thomas Hatch and first released in March 2011. It was designed to address the need for faster, more scalable configuration management and remote execution than existing tools at the time. A key differentiator was its use of ZeroMQ for high-performance communication, enabling near-real-time command execution across thousands of servers. Over the years, <i>Salt</i> has evolved significantly, adding robust state management, orchestration capabilities, cloud integration, and a vibrant open-source community. It was acquired by VMware in October 2020.


title: SYNOPSIS
content:
<b>salt-call</b> <i>[options] &lt;function&gt; [arguments]</i> <br><br><i>Examples:</i><br><b>salt-call</b> <i>cmd.run 'ls -l /tmp'</i><br><b>salt-call</b> <i>state.apply my_state_file</i><br><b>salt-call</b> <i>--local pkg.install apache</i>


title: PARAMETERS
content:
<b>-h, --help</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Display the help message and exit.<br><br><b>-v, --version</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Show program's version number and exit.<br><br><b>-l &lt;level&gt;, --log-level=&lt;level&gt;</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Set the console log level. Possible levels are: <i>debug</i>, <i>info</i>, <i>warning</i>, <i>error</i>, <i>critical</i>.<br><br><b>--local</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Run <b>salt-call</b> locally without connecting to a Salt master. This option causes <b>salt-call</b> to load modules from the local file system.<br><br><b>-c &lt;dir&gt;, --config-dir=&lt;dir&gt;</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specify the directory where the Salt configuration files are located. Default is <i>/etc/salt</i>.<br><br><b>-m &lt;dir&gt;, --module-dirs=&lt;dir&gt;</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specify additional directories where custom Salt execution modules, state modules, or other plugin types can be found.<br><br><b>--output=&lt;outputter&gt;, --out=&lt;outputter&gt;</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specify the outputter to use for displaying results. Common options include <i>json</i>, <i>yaml</i>, <i>raw</i>, <i>highstate</i>, <i>nested</i> (default).<br><br><b>--out-file=&lt;path&gt;</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Write the output of the command to the specified file instead of standard output.<br><br><b>--retcode-passthrough</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Pass through the Salt internal retcode as the shell exit code. Useful for scripting.<br><br><b>--file-root=&lt;path&gt;</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Override the configured file_roots for the Salt minion.<br><br><b>--pillar-root=&lt;path&gt;</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Override the configured pillar_roots for the Salt minion.<br><br><b>--state-tree=&lt;path&gt;</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Override the configured state_tree for the Salt minion (equivalent to <i>file-root</i> for states).<br><br><b>--master=&lt;hostname&gt;</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specify the Salt master to connect to, if not using <b>--local</b>.<br><br><b>--minion-id=&lt;id&gt;</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specify the minion ID to use for the local execution.<br><br>


title: DESCRIPTION
content:
<b>salt-call</b> is a utility included with the SaltStack automation framework, designed to execute Salt functions directly on a Salt minion without requiring a Salt master. It effectively simulates a command originating from a master, allowing for local testing, debugging, and administration. <br><br>This command is invaluable for developers testing new Salt execution modules or states, as well as system administrators who need to apply a Salt state or run a specific Salt function directly on a single machine for verification or troubleshooting. While <b>salt-call</b> typically connects to a local Salt minion daemon to execute commands, the <b>--local</b> option allows it to operate entirely stand-alone, using only local configuration and files, making it perfect for environments where a Salt master isn't present or desired for a particular operation.


title: CAVEATS
content:
When using <b>salt-call</b> without the <b>--local</b> option, it still communicates with the local Salt minion daemon, which might be connected to a Salt master. However, many features typically provided by the master (like master-defined Pillars, Grains, or files from the master's file_roots) will not be available or will behave differently if not configured locally. <br><br>The <b>--local</b> option specifically bypasses any master connection, meaning all necessary configuration, modules, states, and pillar data must be present on the local file system. This distinction is crucial for understanding <b>salt-call</b>'s operational context.


title: FUNCTION INVOCATION
content:
The <i>&lt;function&gt;</i> argument usually follows the format <i>module.function</i> (e.g., <i>pkg.install</i>, <i>state.apply</i>, <i>cmd.run</i>). Arguments to the function are passed directly after the function name.


title: STATE MANAGEMENT
content:
<b>salt-call</b> is frequently used for local state management, such as applying a specific state file (<i>salt-call state.apply my_state_file</i>) or even a full <i>highstate</i> (<i>salt-call state.highstate</i>) directly on the minion. This is extremely useful for testing state changes or applying configurations in isolated environments.


title: DEBUGGING AND DEVELOPMENT
content:
For Salt module developers, <b>salt-call</b> is an indispensable tool. It allows for rapid iteration and testing of new execution modules, state modules, or custom returners by running them directly on a test minion and observing their output without master involvement.


title: HISTORY
content:
<b>salt-call</b> has been an integral part of the SaltStack project since its early public releases around 2011. It was introduced to provide a direct, on-minion method for executing Salt modules and states, initially to aid in debugging and testing new features without needing a full master-minion setup. Over time, its usage expanded significantly, becoming a staple for local system administration, bootstrapping new systems, and developing complex Salt states due to its ability to mimic master commands and its powerful <b>--local</b> mode.


title: SYNOPSIS
content:
<b>salt-key</b> [<i>options</i>] [<i>arguments</i>]<br><br>Common usage patterns:<br><b>salt-key</b> <i>-L</i><br><b>salt-key</b> <i>-a</i> <I>minion_id</I><br><b>salt-key</b> <i>-d</i> <I>minion_id</I><br><b>salt-key</b> <i>-A</i><br><b>salt-key</b> <i>-D</i>


title: PARAMETERS
content:
<b><b>-h</b>, <b>--help</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Show the help message and exit.<br><br><b><b>-V</b>, <b>--version</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Show the program's version number and exit.<br><br><b><b>-c</b> <I>CONFIG_DIR</I>, <b>--config-dir</b>=<I>CONFIG_DIR</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specify the directory for the Salt master configuration files. Defaults to <i>/etc/salt</i>.<br><br><b><b>-L</b>, <b>--list-all</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;List all accepted, pending, and rejected minion keys.<br><br><b><b>-l</b> <I>STATUS</I>, <b>--list</b>=<I>STATUS</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;List keys by their status. <I>STATUS</I> can be <b>pending</b>, <b>accepted</b>, <b>rejected</b>, <b>all</b>, or <b>preaccepted</b>.<br><br><b><b>-a</b> <I>KEY_ID</I>, <b>--accept</b>=<I>KEY_ID</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Accept a specified minion key by its ID.<br><br><b><b>-A</b>, <b>--accept-all</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Accept all currently pending minion keys.<br><br><b><b>-d</b> <I>KEY_ID</I>, <b>--delete</b>=<I>KEY_ID</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Delete a specified minion key by its ID (from pending, accepted, or rejected lists).<br><br><b><b>-D</b>, <b>--delete-all</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Delete all accepted, pending, and rejected minion keys. Use with extreme caution!<br><br><b><b>-r</b> <I>KEY_ID</I>, <b>--reject</b>=<I>KEY_ID</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Reject a specified minion key by its ID, moving it to the rejected list.<br><br><b><b>-R</b>, <b>--reject-all</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Reject all currently pending minion keys.<br><br><b><b>--thumb</b> <I>KEY_ID</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Display the SHA256 thumbprint of a specified key. This is useful for out-of-band verification.<br><br><b><b>--finger</b> <I>KEY_ID</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Display the SHA256 finger (same as thumbprint) of a specified key. Alias for <b>--thumb</b>.<br><br><b><b>-y</b>, <b>--yes</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Assume 'yes' to all questions; non-interactive mode. Use with caution, especially with bulk operations.<br><br><b><b>--key-logfile</b> <I>PATH</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specify a separate log file path for key actions.<br><br>


title: DESCRIPTION
content:
<i>salt-key</i> is a command-line utility for managing Salt minion public keys on a Salt master server. In the SaltStack architecture, minions (client machines) connect to the Salt master (server) using public-key cryptography. When a minion first attempts to connect, it sends its public key to the master. The master, for security reasons, does not automatically accept this key. <i>salt-key</i> provides the interface to review, accept, reject, or delete these pending, accepted, or rejected keys.<br><br>This tool is crucial for maintaining the security and integrity of a SaltStack environment. Administrators use <i>salt-key</i> to authorize new minions, remove decommissioned minions, or re-accept keys for minions that might have had their keys revoked or regenerated. It offers various options for listing keys by their status (pending, accepted, rejected), accepting all pending keys, or acting on specific key IDs. Effective use of <i>salt-key</i> is fundamental for secure and robust SaltStack deployments.


title: CAVEATS
content:
Requires root privileges or appropriate permissions on the Salt master's key directory (typically <i>/etc/salt/pki/master/</i>).<br>Deleting keys (<b>-d</b> or <b>-D</b>) is permanent and will prevent the associated minion from connecting until its key is regenerated and re-accepted.<br>The <b>--yes</b> (<b>-y</b>) option should be used with extreme caution, especially with <b>-A</b>, <b>-D</b>, or <b>-R</b>, as it bypasses crucial confirmation prompts.


title: KEY MANAGEMENT LIFECYCLE
content:
The typical lifecycle of a Salt minion key involves:<br>1. A new Salt minion starts and attempts to connect to the master.<br>2. The minion sends its public key to the master.<br>3. The master lists this key as 'pending' when queried with <b>salt-key -L</b>.<br>4. An administrator verifies the minion's identity and uses <b>salt-key -a <I>minion_id</I></b> (or <b>-A</b>) to accept the key.<br>5. The key moves to the 'accepted' list, allowing the minion to communicate securely with the master.<br>6. If a minion is decommissioned or compromised, its key can be deleted with <b>salt-key -d <I>minion_id</I></b>.


title: SECURITY CONSIDERATIONS
content:
Always verify the identity of a minion before accepting its key. This can be done by cross-referencing the minion's ID and its key's thumbprint (obtained via <b>salt-key --thumb <I>minion_id</I></b>) with information from the minion itself (e.g., from <i>/etc/salt/pki/minion/minion.pem</i> or by running <b>salt-call key.finger</b> on the minion). Accepting unauthorized keys can lead to security vulnerabilities and unauthorized access to your Salt environment.


title: HISTORY
content:
<i>salt-key</i> has been a fundamental component of the SaltStack project since its initial release in 2011 by Thomas Hatch. As secure communication is central to Salt's architecture, key management was an early and essential feature. Its core functionality has remained consistent over time, with ongoing enhancements focused on robustness, clarity of output, and expanded filtering options, reflecting SaltStack's commitment to powerful and user-friendly command-line administration tools.


title: PARAMETERS
content:
<b>-l, --log-level <LEVEL></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Set the console log reporting level to <I>LEVEL</I> (e.g., <I>info</I>, <I>warning</I>, <I>error</I>, <I>debug</I>).<br><br><b>-o, --output <FORMAT></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specify the output format for the command's return data (e.g., <I>json</I>, <I>yaml</I>, <I>pprint</I>, <I>raw</I>).<br><br><b>-t, --timeout <SECONDS></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Set the timeout in seconds for runner execution. Defaults to 60 seconds.<br><br><b>-c, --config-dir <PATH></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specify the path to the Salt configuration directory. Defaults to <I>/etc/salt</I>.<br><br><b>--local</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Execute in local mode, without requiring a Salt master. This is mainly for testing or specific standalone operations.<br><br><b>--versions-report</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Display program version and exit.<br><br><b>-h, --help</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Show the program's help message and exit.<br><br>


title: DESCRIPTION
content:
The <b>salt-run</b> command is a utility within the <I>SaltStack</I> automation and configuration management system. It is specifically designed to execute <I>runner modules</I> directly on the Salt master server. Unlike the primary <I>salt</I> command, which sends commands to Salt minions, <I>salt-run</I> operates master-side to perform administrative, analytical, or orchestration tasks that do not require minion interaction. Common uses include managing Salt keys, querying the master's status, orchestrating multi-minion deployments, or executing custom administrative scripts defined as runner modules. It provides a powerful interface for managing the Salt infrastructure itself.


title: CAVEATS
content:
<b>Execution Context:</b> <I>salt-run</I> commands are executed on the Salt master server, not on minions.<br><b>Permissions:</b> The user executing <I>salt-run</I> on the master needs appropriate file system and Salt configuration permissions to access runner modules and master-side resources.<br><b>Impact:</b> Runners can perform powerful operations (e.g., key deletion, orchestration of states). Use with caution and ensure you understand the runner's function.<br><b>Dependency on Master:</b> Typically requires a running Salt master daemon, unless the <I>--local</I> flag is used for specific testing scenarios.


title: RUNNER MODULES EXPLAINED
content:
Runner modules are Python modules located on the Salt master (typically in <I>/srv/salt/_runners</I> or directories specified in the master config). They contain functions designed to be executed directly by the Salt master to perform master-side operations. These modules are not executed by minions.


title: COMMON USE CASES
content:
Some frequent applications of <I>salt-run</I> include:<br><b>Key Management:</b> E.g., <I>salt-run manage.up</I> (list connected minions), <I>salt-run manage.down</I> (list disconnected minions), <I>salt-run manage.raw_minions</I> (list all minions known by the master).<br><b>Orchestration:</b> E.g., <I>salt-run state.orch my.orchestration.state</I> (execute a Salt orchestration state on the master).<br><b>Master Status/Maintenance:</b> E.g., <I>salt-run cache.clear_all</I> (clear all master-side minion caches).<br><b>External Authentication (eAuth):</b> Runners can be used in conjunction with eAuth systems to provide controlled access to Salt functionality.


title: HISTORY
content:
SaltStack was initially released in 2011, and <I>salt-run</I> has been a fundamental component since its early versions. It was conceived to provide a distinct interface for master-side administrative tasks, separating them from minion-targeting operations. Over time, as SaltStack's capabilities expanded, so did the variety and complexity of available runner modules, solidifying <I>salt-run</I>'s role as a critical tool for managing Salt infrastructure and orchestrating complex deployments.


title: PARAMETERS
content:
<b>file ...</b><br>&nbsp;&nbsp;&nbsp;&nbsp;One or more files to be opened for editing upon startup.<br><br><b>-r</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Open files in read-only mode, preventing accidental writes.<br><br><b>-d</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Detach <i>sam</i> from the controlling terminal, often used for server mode.<br><br><b>-s</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Start <i>sam</i> as a server, allowing other clients to connect to it.<br><br><b>-i <i>command</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Execute the specified <i>sam</i> command string after startup.<br><br>


title: DESCRIPTION
content:
The <i>Sam</i> editor is a powerful and unique text editor originating from Bell Labs' Plan 9 operating system, designed by Rob Pike. Unlike typical line-oriented or screen-oriented editors, <i>Sam</i> emphasizes a structural approach to text manipulation through its integrated command language and powerful regular expressions, often referred to as 'structural regular expressions'. It excels at complex, programmatic text transformations across multiple files or large documents. While not a standard utility on most mainstream Linux distributions, <i>Sam</i> can be compiled and run on Linux systems, offering an alternative editing paradigm for those accustomed to its Plan 9 philosophy or seeking its distinct capabilities for scripting text edits.


title: CAVEATS
content:
<i>Sam</i> is not a standard utility on most mainstream Linux distributions and typically needs to be compiled from source or installed from specialized repositories. Its unique command language and interaction model can have a steep learning curve for users accustomed to more conventional editors like <i>Vim</i> or <i>Emacs</i>. Its primary strength lies in programmatic text manipulation rather than simple interactive editing, which might not suit all users or workflows.


title: COMMAND LANGUAGE AND STRUCTURAL REGULAR EXPRESSIONS
content:
<i>Sam</i>'s power largely stems from its internal command language, which allows complex text manipulations using sequences of commands. A core concept is 'structural regular expressions', which extends traditional regular expressions to operate on arbitrarily large textual structures, enabling powerful and precise selection of text regions for editing. This feature makes <i>Sam</i> particularly effective for batch processing or scripting complex text transformations.


title: HISTORY
content:
The <i>Sam</i> text editor was designed by Rob Pike at Bell Labs for the Plan 9 operating system, with its initial public release occurring around the late 1980s. It was conceived as an improvement over traditional line editors like <i>ed</i>, combining a powerful command language with structural regular expressions and a mouse-driven interface. Its development was deeply intertwined with the philosophy of Plan 9, emphasizing simplicity, clear interfaces, and composability. While primarily a Plan 9 tool, its unique design led to ports and implementations on other Unix-like systems, including Linux, preserving its distinct approach to text editing outside its native environment.


title: PARAMETERS
content:
<b>-o <file></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the output filename.<br><br><b>-f <format></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets the output format (e.g., ps, pdf, png, jpg, tiff, gif, bmp, ppm).<br><br><b>-r <resolution></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets the output resolution for raster formats in DPI.<br><br><b>-s <scale></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Applies a scaling factor to the output.<br><br><b>-c <file></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies an alternative configuration file for plotting.<br><br><b>-t <title></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Adds a custom title to the plot.<br><br><b>-l</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Forces landscape orientation for the output.<br><br><b>-P</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Forces portrait orientation for the output.<br><br><b>-w <width></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets the output width in inches (for vector) or pixels (for raster).<br><br><b>-H <height></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets the output height in inches (for vector) or pixels (for raster).<br><br><b>-p <pages></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies a range of pages to convert (e.g., '1-5', '2,4').<br><br><b>-bg <color></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets the background color (e.g., 'white', '#RRGGBB').<br><br><b>-fg <color></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets the foreground color.<br><br><b>-x <offset></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies an X-offset for the plot on the page.<br><br><b>-y <offset></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies a Y-offset for the plot on the page.<br><br><b>-v</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays the version information and exits.<br><br><b>-h</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays a brief help message and exits.<br><br>


title: DESCRIPTION
content:
sam2p is a specialized command-line utility used for converting display files generated by the <I>SAD (Seismic Analysis Display)</I> software suite into various standard graphics formats. These display files typically contain visualizations of seismic data, such as traces, sections, and plots.<br><br>sam2p enables users to transform these specialized data representations into widely accessible formats like <I>PostScript</I> (.ps), <I>PDF</I> (.pdf), <I>PNG</I> (.png), <I>JPEG</I> (.jpg), <I>TIFF</I> (.tif), <I>GIF</I> (.gif), <I>BMP</I> (.bmp), and <I>PPM</I> (.ppm). This conversion is crucial for sharing, printing, or embedding seismic visualizations into reports and presentations, bridging the gap between specialized scientific software and general-purpose document and image handling tools. It offers control over output resolution, scaling, page layout, and various other graphical parameters.


title: CAVEATS
content:
sam2p is highly specialized, primarily designed for converting files produced by the <I>SAD</I> (Seismic Analysis Display) software suite. It is not a general-purpose image or document converter like <I>ImageMagick</I> or <I>Ghostscript</I> and cannot process arbitrary image or document types. Its utility is limited to the specific display file formats generated by the <I>SAM</I> and <I>SAD</I> programs. Proper functioning, especially for PostScript and PDF output, often depends on external tools like <I>Ghostscript</I> being installed and accessible.


title: INPUT FORMATS
content:
<I>sam2p</I> primarily processes display files generated by the <I>SAD</I> and <I>SAM</I> software, which are specialized binary or ASCII formats representing seismic traces, plots, and graphical elements. These files are typically created as output from seismic data processing and visualization workflows within the SAD environment.


title: OUTPUT FORMATS
content:
The command supports a variety of output formats including vector graphics (PostScript, PDF) for high-quality printing and scalability, and raster image formats (PNG, JPEG, TIFF, GIF, BMP, PPM) suitable for web, screen display, and common image manipulation. The choice of format depends on the intended use case, with vector formats preferred for print and raster for general digital sharing.


title: HISTORY
content:
<I>sam2p</I> is an integral component of the <I>SAD (Seismic Analysis Display)</I> software suite, which originated in academic and geophysical research environments for the visualization and analysis of seismic data. Developed to address the specific need for converting specialized graphical output from seismic processing into standard printable and viewable formats, <I>sam2p</I> has been a stable tool within this niche community for decades. Its development has focused on maintaining compatibility with the evolving SAD data formats and supporting a range of common graphical output standards.


title: PARAMETERS
content:
<b><b>-D</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;<i>Runs the Samba daemon in the background.</i><br><br><b><b>-F</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;<i>Runs the Samba daemon in the foreground, useful for debugging.</i><br><br><b><b>-s</b> <i>&lt;configfile&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;<i>Specifies an alternative configuration file to use instead of the default `/etc/samba/smb.conf`.</i><br><br><b><b>-l</b> <i>&lt;logdirectory&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;<i>Directs log files to the specified directory.</i><br><br><b><b>-V</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;<i>Prints the Samba version number and exits.</i><br><br><b><b>-i</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;<i>Runs the daemon in interactive mode (usually with <b>-F</b>).</i><br><br>


title: DESCRIPTION
content:
Samba is a Free Software re-implementation of the SMB/CIFS networking protocol, which is the standard file sharing protocol used by Microsoft Windows. It allows Unix/Linux systems to seamlessly interoperate with Windows clients and servers. <br><br>The primary function of Samba is to provide file and print services to Windows clients, acting as a server. It also enables Unix/Linux clients to access shares on Windows servers. Beyond simple file/print sharing, Samba can function as an Active Directory Domain Controller (AD DC), providing authentication, authorization, and directory services for Windows and Linux clients in an enterprise network. This integration involves various components like `smbd` (SMB server), `nmbd` (NetBIOS name server), and `winbindd` (user/group integration). The `samba` command itself often refers to the main daemon when running as an AD DC.


title: CAVEATS
content:
Configuring Samba, especially as an Active Directory Domain Controller, can be complex and requires a deep understanding of networking, authentication, and directory services. Large deployments demand significant system resources. Proper security configuration, including ACLs and firewall rules, is crucial to prevent unauthorized access. Troubleshooting can be challenging due to the intricate interaction of various protocols and components.


title: CONFIGURATION FILE
content:
The primary configuration file for Samba is typically located at <i>/etc/samba/smb.conf</i>. This file defines shares, security settings, logging parameters, and the overall behavior of Samba services.


title: SAMBA ROLES
content:
Samba can operate in various roles: as a <i>standalone server</i> (simple file/print sharing), a <i>member server</i> (joining an existing Windows or Samba domain), an <i>NT4-style Primary Domain Controller (PDC)</i>, or as an <i>Active Directory Domain Controller (AD DC)</i>, providing full domain services including Kerberos, LDAP, and DNS.


title: HISTORY
content:
Samba was originally developed by Andrew Tridgell in 1992, initially named "smbserver". It began as a re-implementation of the SMB protocol for SunOS. Over decades, it has evolved significantly, adding support for various Windows features including NetBIOS, WINS, Active Directory, and more recent SMB protocol versions (SMB2/3). A major milestone was the release of Samba 4.0, which introduced the capability to function as a full-fledged Active Directory Domain Controller, allowing Linux servers to seamlessly integrate into Windows domains without requiring Windows Server licenses. Its continuous development by a global community has made it a cornerstone for mixed-environment interoperability.


title: SEE ALSO
content:
smbd(8), nmbd(8), winbindd(8), smbclient(1), smbpasswd(8), net(8), testparm(1), samba-tool(8), rpcclient(1)


title: PARAMETERS
content:
<b><b>--help</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays the help message and exits.<br><br><b><b>--file</b>=<i>&lt;ldb_file&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the LDB file to operate on. If not specified, it typically defaults to <i>sam.ldb</i> for an AD DC.<br><br><b><b>--machine</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Authenticates using machine credentials. Useful when running on a domain member or DC.<br><br><b><b>--user</b>=<i>&lt;username&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the username for authentication. Requires <i>Domain Admin</i> privileges for most operations.<br><br><b><b>--password</b>=<i>&lt;password&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the password for the given username. For security, it's often better to omit this and be prompted.<br><br><b><b>import</b> <i>&lt;filename&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Imports registry data from a specified <i>.reg</i> file. The file content should be in the standard Windows registry format.<br><br><b><b>export</b> <i>&lt;filename&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Exports the specified registry key or the entire registry to a <i>.reg</i> file.<br><br><b><b>query</b> <i>&lt;key_path&gt;</i> [<i>&lt;value_name&gt;</i>]</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Queries and displays the content of a specific registry key or a named value within it.<br><br><b><b>add</b> <i>&lt;key_path&gt;</i> <i>&lt;value_name&gt;</i> <i>&lt;type&gt;</i> <i>&lt;data&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Adds a new registry key or a new value to an existing key. <i>&lt;type&gt;</i> can be REG_DWORD, REG_SZ, REG_MULTI_SZ, etc.<br><br><b><b>set</b> <i>&lt;key_path&gt;</i> <i>&lt;value_name&gt;</i> <i>&lt;data&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets (modifies) the data for an existing registry value.<br><br><b><b>delete</b> <i>&lt;key_path&gt;</i> [<i>&lt;value_name&gt;</i>]</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Deletes a specified registry key (and all its subkeys/values) or a specific value within a key.<br><br><b><b>enum-keys</b> <i>&lt;key_path&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Enumerates and lists all subkeys directly under the specified <i>&lt;key_path&gt;</i>.<br><br><b><b>enum-values</b> <i>&lt;key_path&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Enumerates and lists all values directly under the specified <i>&lt;key_path&gt;</i>.<br><br>


title: DESCRIPTION
content:
<i>samba-regedit</i> is a powerful command-line utility within the Samba suite designed for advanced administrators to directly inspect and modify Samba's internal registry. Unlike the <i>smb.conf</i> file, which handles many common configurations, <i>samba-regedit</i> allows for direct manipulation of registry keys and values that Samba uses for its Active Directory Domain Controller (AD DC) functionality and other internal settings. <br><br>It operates on the underlying LDB (Lightweight Directory B-tree) database files (such as <i>sam.ldb</i>) that store Samba's configuration and Active Directory objects. This tool supports operations similar to Windows' <i>Regedit</i>, including importing/exporting <i>.reg</i> files, querying keys, and adding, setting, or deleting values. Due to its direct interaction with critical Samba databases, it should be used with extreme caution and only by experienced users.


title: CAVEATS
content:
<b><i>EXTREME CAUTION ADVISED:</i></b> This tool directly modifies Samba's internal databases. Incorrect usage can lead to data corruption, loss of configuration, or complete failure of Samba services, especially an Active Directory Domain Controller.<br><br><b><i>Backup First:</i></b> Always back up your critical LDB files (e.g., <i>/var/lib/samba/private/sam.ldb</i>) before making any changes.<br><br><b><i>Privileges:</i></b> Requires root privileges or a Samba <i>Domain Admin</i> account to operate effectively.<br><br><b><i>Service Restart:</i></b> Many changes made via <i>samba-regedit</i> will require a restart of Samba services (e.g., <i>samba-ad-dc.service</i>) to take effect.


title: REGISTRY STRUCTURE
content:
Samba's internal registry often emulates parts of the Windows registry hierarchy, especially keys relevant to services, security, and software configurations. Common root keys include <i>HKEY_LOCAL_MACHINE</i> and sometimes <i>HKEY_CURRENT_USER</i> (though the latter is less frequently manipulated via <i>samba-regedit</i>).


title: LDB BACKEND EXPLAINED
content:
The 'registry' that <i>samba-regedit</i> interacts with is not a traditional flat file but a structured LDB database. <i>samba-regedit</i> translates the familiar registry operations (add, delete, query) into corresponding LDB database operations, making complex LDB manipulation more accessible for users familiar with Windows registry concepts.


title: COMMON USE CASES
content:
While most Samba configuration is done in <i>smb.conf</i>, <i>samba-regedit</i> is used for specific advanced scenarios such as: <br><ul><li>Enabling/disabling specific internal Samba features not exposed elsewhere.</li><li>Modifying advanced security settings or logging levels.</li><li>Troubleshooting complex Active Directory replication or authentication issues.</li><li>Implementing very specific registry-based group policies or application settings within the AD environment.</li></ul>


title: HISTORY
content:
With the advent of Samba 4 and its capabilities as an Active Directory Domain Controller, Samba needed a mechanism to manage its own internal 'registry' that mirrored parts of the Windows registry for AD objects and other system-wide settings. This internal data is stored in LDB (Lightweight Directory B-tree) databases. <i>samba-regedit</i> was developed as a command-line interface to provide a familiar 'Regedit'-like experience for administrators to interact with these LDB-backed registry settings, offering direct control over configurations not typically exposed through <i>smb.conf</i> or the simpler <i>net</i> commands. It has been a part of the Samba 4 toolset since its early development to facilitate advanced configuration and troubleshooting for Samba AD DCs.


title: PARAMETERS
content:
<b><b>--help</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays help information for <i>samba-tool</i> or its specific commands/subcommands.<br><br><b><b>--version</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Shows the version information of the <i>samba-tool</i> utility.<br><br><b><b>-k</b> | <b>--kerberos=METHOD</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the Kerberos authentication method to use for the operation.<br><br><b><b>--realm=REALM</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Defines the Kerberos realm to authenticate against.<br><br><b><b>-H</b> | <b>--url=URL</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the LDAP URL for connecting to the domain controller, e.g., ldap://dc1.example.com.<br><br><b><b>-U</b> | <b>--user=USERNAME</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Provides the username for authentication. Often used with <b>--password</b>.<br><br><b><b>-W</b> | <b>--workgroup=WORKGROUP</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the workgroup or domain for the user account during authentication.<br><br><b><b>-P</b> | <b>--password=PASSWORD</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Supplies the password for the specified username. Use with caution for security reasons.<br><br><b><b>-N</b> | <b>--no-pass</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Prevents <i>samba-tool</i> from prompting for a password, useful when using Kerberos or other authentication methods.<br><br><b><b>-S</b> | <b>--server=SERVER</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the target domain controller by its hostname or FQDN.<br><br><b><b>-I</b> | <b>--ipaddress=IPADDRESS</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the IP address of the target domain controller.<br><br><b><b>--bind=BINDDN</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the Distinguished Name (DN) to bind as for LDAP operations.<br><br><b><b>--aeskey=KEY</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Provides an AES key for authentication, typically for automated scripts.<br><br><b><b>--pwreqs=YES|NO</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Controls whether password complexity requirements are enforced for user account operations.<br><br><b><b>-d</b> | <b>--debuglevel=DEBUGLEVEL</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets the debug logging level (0-10) for verbose output to assist in troubleshooting.<br><br>


title: DESCRIPTION
content:
<i>samba-tool</i> is the primary command-line utility for administering a Samba Active Directory Domain Controller (AD DC). It provides a unified interface for managing various aspects of the domain, including users, groups, computers, DNS records, GPOs, and replication. Before its introduction, administration of Samba AD DC often required a mix of various tools, some specific to Samba and others generic LDAP or DNS utilities. <i>samba-tool</i> consolidates these functions, making management more consistent and straightforward. It interacts directly with the Samba AD DC's LDAP directory and other backend services, simplifying complex operations like adding domain members, managing trusts, or promoting/demoting domain controllers. Its comprehensive nature makes it an indispensable tool for anyone managing a Samba-based Active Directory environment.


title: CAVEATS
content:
Most <i>samba-tool</i> operations require root privileges or equivalent administrative permissions on the Samba AD DC. It is primarily designed for managing Samba Active Directory Domain Controllers; its functionality is limited or irrelevant on standalone or member servers. Operations directly modify the AD database, so caution is advised, especially in production environments. Authentication typically relies on Kerberos; explicit <b>--user</b> and <b>--password</b> are alternatives for scripting or remote access.


title: AUTHENTICATION AND CONNECTIVITY
content:
<i>samba-tool</i> heavily relies on Kerberos for authentication. When executed directly on the DC, it often operates without explicit credentials due to Kerberos ticket availability. For remote execution or scripting, proper Kerberos setup (e.g., using <i>kinit</i> for a privileged user) or explicit <b>--user</b>/<b>--password</b> options are necessary. It connects to the DC's LDAP service, usually on port 389 or 636 (LDAPS).


title: LOGGING AND DEBUGGING
content:
For troubleshooting issues, increasing the debug level using <b>-d</b> or <b>--debuglevel</b> can provide verbose output directly to the console or logs. Detailed information about <i>samba-tool</i> operations, including errors and warnings, is typically logged in Samba's main log files, found under <i>/var/log/samba/</i>, often named <i>log.samba</i> or <i>log.ldb</i>.


title: HISTORY
content:
<i>samba-tool</i> was introduced as a cornerstone utility with the Samba 4.0 release. This major milestone allowed Samba to function as a full-fledged Active Directory Domain Controller. Prior to Samba 4, administrative tasks were often disparate, relying on a mix of tools like <i>smbpasswd</i>, <i>net</i>, <i>ldbtools</i>, and manual LDAP operations. The development of <i>samba-tool</i> aimed to consolidate these administrative tasks into a single, consistent, and user-friendly command-line interface, providing a unified management experience akin to Microsoft's AD management utilities. Its introduction significantly simplified the deployment and ongoing management of Samba AD DCs, making it a critical component of the Samba project.


title: SYNOPSIS
content:
<b>samtools</b> <I>command</I> [<i>options</i>] [<i>arguments</i>]<br><br><i>samtools</i> operates via subcommands. To see a list of available subcommands, run <b>samtools</b> without any arguments or with <b>samtools help</b>. For help on a specific subcommand, use <b>samtools help</b> <I>command</I>.<br><br>Some frequently used subcommands include:<br>&nbsp;&nbsp;<b>view</b>: View, convert, and filter alignments.<br>&nbsp;&nbsp;<b>sort</b>: Sort alignments by coordinate or query name.<br>&nbsp;&nbsp;<b>index</b>: Index BAM/CRAM files for fast random access.<br>&nbsp;&nbsp;<b>merge</b>: Merge multiple sorted alignment files.<br>&nbsp;&nbsp;<b>mpileup</b>: Generate a pileup from alignment files.<br>&nbsp;&nbsp;<b>flagstat</b>: Compute flag statistics.<br>&nbsp;&nbsp;<b>depth</b>: Compute the depth of coverage.<br>&nbsp;&nbsp;<b>faidx</b>: Index/query FASTA reference sequence files.


title: PARAMETERS
content:
<b><i>(General Note)</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Parameters are subcommand-specific. The options below are common for the <b>view</b> subcommand, used for extracting, filtering, and converting alignment files.<br><br><b>-b</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Output in BAM format.<br><br><b>-S</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Input is SAM format (default is auto-detected).<br><br><b>-h</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Include header in the output.<br><br><b>-o <file></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Write output to <file> (default: standard output).<br><br><b>-f <int></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Only output alignments with all bits in <int> present in the FLAG field.<br><br><b>-F <int></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Skip alignments with any bits in <int> present in the FLAG field.<br><br><b>-q <int></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Only output alignments with mapping quality greater than or equal to <int>.<br><br><b>-@ <int></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Set number of additional threads to use for I/O and compression.<br><br><b>-L <file></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Only output alignments overlapping regions specified in <file> (BED format).<br><br>


title: DESCRIPTION
content:
<i>samtools</i> is a comprehensive suite of utilities designed for interacting with high-throughput sequencing data in SAM, BAM, and CRAM formats. These formats store biological sequence alignments, which are crucial outputs from next-generation sequencing (NGS) experiments. The toolkit provides essential functionalities for managing and manipulating these large files efficiently. Key operations include viewing and converting file formats, sorting alignments by coordinate or query name, merging multiple alignment files, and creating indexes for fast random access to specific genomic regions. It also enables generation of pileups, calculation of alignment statistics, and extraction of subsets of data. Built upon the HTSlib library, <i>samtools</i> is a cornerstone tool in bioinformatics workflows, widely used for quality control, variant calling preparation, and general data exploration.


title: CAVEATS
content:
<i>samtools</i> operations, especially sorting large files, can be memory and disk I/O intensive. Users should ensure sufficient system resources. For CRAM files and certain operations like <b>mpileup</b>, a reference genome FASTA file is often required. Random access to BAM/CRAM files relies on a separate index file (e.g., .bam.bai or .cram.crai) generated by <b>samtools index</b>, which must be present in the same directory as the alignment file.


title: HTSLIB FOUNDATION
content:
<i>samtools</i> is built on top of the HTSlib library, a C library for reading/writing high-throughput sequencing data formats. This foundation provides <i>samtools</i> with its high performance and robust capabilities for handling large genomic datasets efficiently, often outperforming other tools for similar tasks.


title: INDEXING FOR PERFORMANCE
content:
To enable fast random access to specific regions within large BAM or CRAM files, an index file (e.g., .bam.bai or .cram.crai) must be created using the <b>samtools index</b> subcommand. Without an index, operations requiring random access (like viewing a specific genomic region or generating pileups) would need to scan the entire file, which is highly inefficient for large datasets.


title: HISTORY
content:
<i>samtools</i> was originally developed by Heng Li as a command-line utility for the MAQ alignment software package. As the SAM/BAM format gained widespread adoption as the standard for high-throughput sequencing data, <i>samtools</i> was spun off into a standalone project to provide a dedicated, high-performance toolkit for managing these files. Its development closely paralleled the growth of NGS, quickly becoming an indispensable tool in bioinformatics pipelines. It is now maintained as an open-source project, primarily on GitHub, and is tightly integrated with the HTSlib C library, which provides robust and efficient routines for SAM, BAM, and CRAM file manipulation.


title: SYNOPSIS
content:
<b>sane-find-scanner</b> [<i>options</i>]<br><b>sane-find-scanner</b> [<b>-q</b>] [<b>-g</b>] [<b>-f</b>] [<b>-p</b>] [<b>-v</b>] [<b>-s</b>] [<b>-V</b>]


title: PARAMETERS
content:
<b><b>-q</b>, <b>--quiet</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Suppresses output for successfully found devices. Only errors or warnings are printed. Useful for scripting.<br><br><b><b>-g</b>, <b>--list-groups</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Lists the Unix group IDs that SANE backends would typically try to use for device access (e.g., 'scanner'). This helps in configuring user permissions.<br><br><b><b>-f</b>, <b>--no-forceread</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;By default, <i>sane-find-scanner</i> attempts to read a few bytes from certain devices to verify they are scanners. This option disables that behavior, potentially speeding up detection but might miss some devices that don't respond immediately.<br><br><b><b>-p</b>, <b>--ping</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;For network-attached scanners, this option attempts to ping the detected IP addresses to verify they are active and reachable on the network. This is not for general device detection but for checking network connectivity.<br><br><b><b>-v</b>, <b>--verbose</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Increases the verbosity of the output. More detailed information about the scanning process, devices probed, and any encountered issues will be displayed. Very helpful for debugging.<br><br><b><b>-s</b>, <b>--scsi</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Limits the search to SCSI scanners only. Useful when you know your scanner is SCSI and want to avoid checking other interfaces.<br><br><b><b>-V</b>, <b>--version</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Prints the version information of the <i>sane-find-scanner</i> utility and exits.<br><br>


title: DESCRIPTION
content:
<i>sane-find-scanner</i> is a utility that searches for scanners connected to the system. It inspects common device locations for SCSI, USB, and parallel port (ECP/EPP) based scanners. Its primary purpose is to help users identify if their scanner is detected by the operating system and to provide information (like device files or USB vendor/product IDs) that is crucial for configuring the SANE (Scanner Access Now Easy) backend drivers.<br><br>While it doesn't perform actual scanning, it's an indispensable first step in diagnosing scanner connectivity issues and setting up SANE. It reports found devices, indicating their type and the necessary device paths or identifiers that can then be used in SANE configuration files (e.g., in <i>/etc/sane.d/</i>). A typical use case is running it after connecting a new scanner to verify detection before attempting to scan with tools like <i>scanimage</i> or graphical frontends.


title: CAVEATS
content:
To detect all types of scanners, especially USB and SCSI devices, <i>sane-find-scanner</i> often needs to be run with root privileges (e.g., using <i>sudo</i>). If run as a regular user, it might only find network scanners or devices for which the user already has direct access permissions.<br><br><i>sane-find-scanner</i> identifies potential scanner devices but does not configure them. After detection, manual configuration of SANE backend files (like <i>/etc/sane.d/*.conf</i>) and user permissions (e.g., adding user to 'scanner' group or configuring udev rules) is usually required to make the scanner usable by SANE frontends.


title: PERMISSIONS AND TROUBLESHOOTING
content:
One of the most common reasons <i>sane-find-scanner</i> fails to detect a connected scanner, particularly USB or SCSI devices, is insufficient user permissions. Running the command as a regular user might only show network scanners or devices where proper udev rules and group memberships (e.g., being part of the 'scanner' group) are already in place.<br><br>If your scanner is not detected, first try running <i>sane-find-scanner</i> with <i>sudo</i>. If it appears then, it indicates a permissions issue. You'll need to adjust udev rules or add your user to the appropriate group (often 'scanner' or 'lp') to grant access without root privileges for everyday use. It's an essential diagnostic tool before delving into backend-specific configurations.


title: OUTPUT INTERPRETATION
content:
The output of <i>sane-find-scanner</i> provides crucial information. For USB devices, it typically shows 'found USB scanner (vendor=0x####, product=0x####) at libusb:###:###'. These vendor and product IDs are necessary for configuring the <i>sane-usb</i> backend. For SCSI, it might show 'found SCSI scanner /dev/sg#'. For network scanners, it provides the IP address. This output directly informs how you should edit the corresponding SANE backend configuration files.


title: HISTORY
content:
<i>sane-find-scanner</i> is a core component of the SANE (Scanner Access Now Easy) project, which was initiated in the late 1990s to provide a standard application programming interface (API) for accessing raster image scanners on Unix-like operating systems. As scanner hardware diversified across SCSI, USB, and parallel interfaces, the need for a robust detection utility became paramount. <i>sane-find-scanner</i> was developed early on as a foundational tool to help users and system administrators identify and verify scanner hardware presence, making it a critical first step in the SANE configuration and troubleshooting workflow, a role it continues to play today.


title: PARAMETERS
content:
<b><b>-a</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Auto-enable. Used when <i>saned</i> is run by a super-server (like <i>inetd</i> or <i>xinetd</i>) to automatically enable debugging and logging.<br><br><b><b>-d</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Debug mode. Increases the verbosity of log messages, showing more details about internal operations. Can be specified multiple times (e.g., <b>-dd</b>) for even more verbose output.<br><br><b><b>-o</b> <i>outfile</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Output file. Redirects debugging and other log messages to the specified <i>outfile</i> instead of standard error.<br><br><b><b>-u</b> <i>username</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Run as user. Changes the user ID of the <i>saned</i> process to <i>username</i> after binding to the SANE port. This is a security measure, typically used when <i>saned</i> is started as root.<br><br>


title: DESCRIPTION
content:
The <i>saned</i> command provides a network daemon that allows remote clients to access scanners connected to the local machine. It is part of the SANE (Scanner Access Now Easy) project, which offers a standardized API for accessing various scanning devices. When <i>saned</i> is running, SANE-enabled client applications (such as <i>scanimage</i> or <i>xsane</i>) on remote machines can connect to the host running <i>saned</i> and utilize its locally connected scanners as if they were directly attached. This is particularly useful for sharing a single scanner among multiple users or computers on a network.<br><br><i>saned</i> typically listens on a well-known port (TCP 6566) for incoming connections, receives scanning requests from clients, passes them to the appropriate local SANE backend (driver) for the scanner, and returns the scan data back to the client. It can be run as a standalone daemon or managed by super-servers like <i>inetd</i> or <i>xinetd</i>.


title: CAVEATS
content:
Configuring <i>saned</i> requires careful attention to network security. By default, it may allow access from any host if not properly configured in <i>saned.conf</i>. It's crucial to restrict access to trusted clients or networks to prevent unauthorized use of the scanner or potential security vulnerabilities. Firewall rules must also be configured to allow incoming connections on the SANE port (TCP 6566) for clients to reach <i>saned</i>. Running <i>saned</i> as root and failing to drop privileges via the <b>-u</b> option can also pose a security risk.


title: CONFIGURATION FILES
content:
The primary configuration file for <i>saned</i> is <i>/etc/sane.d/saned.conf</i>. This file controls which client IP addresses or hostnames are allowed to connect to the <i>saned</i> server. It also specifies other options, such as the user under which <i>saned</i> should run if not specified on the command line. Proper configuration of this file is essential for both functionality and security.<br><br>The SANE backend configuration files, located in <i>/etc/sane.d/</i> (e.g., <i>epson.conf</i>, <i>net.conf</i>), also play a role as <i>saned</i> relies on these to find and communicate with local scanners.


title: TYPICAL USAGE AND DEPLOYMENT
content:
<i>saned</i> can be deployed in two main ways:<br>1. <b>Super-server management:</b> This is the most common method. <i>inetd</i> or <i>xinetd</i> listens for incoming connections on the SANE port and then launches a <i>saned</i> instance for each connection. This conserves resources as <i>saned</i> only runs when needed. Configuration usually involves adding an entry to <i>/etc/services</i> and <i>/etc/inetd.conf</i> or <i>/etc/xinetd.d/saned</i>.<br>2. <b>Standalone daemon:</b> <i>saned</i> can be run directly as a persistent daemon. This might be preferred in high-traffic environments where the overhead of launching <i>saned</i> for each connection is undesirable. When run standalone, it typically needs to be started at boot time and manages multiple concurrent connections itself.


title: DEBUGGING
content:
When troubleshooting issues with <i>saned</i>, enabling debug mode (<b>-d</b> or <b>-dd</b>) is crucial. If <i>saned</i> is managed by a super-server, you might need to use the <b>-a</b> option to enable auto-debugging, which logs output to a file (specified with <b>-o</b>). Examining the debug output can help identify problems related to network connectivity, permissions, scanner detection, or backend communication. Ensure that logging is redirected to a writable file if running as a non-privileged user.


title: HISTORY
content:
The SANE (Scanner Access Now Easy) project, which includes <i>saned</i>, began in the mid-1990s with the goal of providing a standardized API for scanner hardware. <i>saned</i> was developed to extend this functionality over networks, allowing remote access to scanners. Its core function has remained consistent since its inception, evolving primarily in terms of robustness, security features, and support for new SANE backends.


title: SEE ALSO
content:
<i>sane-backends</i>(7), <i>saned.conf</i>(5), <i>scanimage</i>(1), <i>xsane</i>(1), <i>inetd</i>(8), <i>xinetd</i>(8)


title: SYNOPSIS
content:
<b>sar</b> [<i>options</i>] [<i>interval</i> [<i>count</i>]]<br>Common examples:<br><b>sar -u</b> <i>interval</i> <i>count</i> (CPU usage)<br><b>sar -r</b> <i>interval</i> <i>count</i> (Memory usage)<br><b>sar -b</b> <i>interval</i> <i>count</i> (I/O statistics)<br><b>sar -n DEV</b> <i>interval</i> <i>count</i> (Network device stats)<br><b>sar -f</b> <i>filename</i> (Read from saved file)


title: PARAMETERS
content:
<b>-u</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Report CPU utilization statistics.<br><br><b>-r</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Report memory and swap space utilization statistics.<br><br><b>-b</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Report I/O and transfer rate statistics.<br><br><b>-d</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Report disk activity statistics (for each disk).<br><br><b>-n <i>{keyword}</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Report network statistics based on <i>keyword</i> (e.g., <i>DEV</i>, <i>IP</i>, <i>TCP</i>).<br><br><b>-w</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Report task creation and context switching statistics.<br><br><b>-q</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Report queue length and load average statistics.<br><br><b>-f <i>{filename}</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Read activity from <i>filename</i> instead of real-time data.<br><br><b>-s <i>{hh:mm:ss}</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Set the start time of data collection.<br><br><b>-e <i>{hh:mm:ss}</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Set the end time of data collection.<br><br><b>-A</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Report all activities (a comprehensive report).<br><br><b><i>interval</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Time in seconds between each report (for real-time).<br><br><b><i>count</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Number of reports to display (for real-time).<br><br>


title: DESCRIPTION
content:
<i>sar</i> (System Activity Reporter) is a powerful command-line utility used for collecting, reporting, and saving system activity information. It is part of the <b>sysstat</b> package. <i>sar</i> provides a comprehensive overview of system performance metrics, including CPU utilization, memory and swap space usage, disk I/O, network statistics, and much more.<br><br>It can display real-time performance data or analyze historical data stored in binary log files, typically located in <i>/var/log/sysstat/</i>. This capability makes <i>sar</i> invaluable for troubleshooting performance bottlenecks, capacity planning, and long-term system monitoring. Administrators often use <i>sar</i> to identify trends, pinpoint periods of high resource consumption, and understand the overall health and behavior of their Linux systems.


title: CAVEATS
content:
<i>sar</i> collects data in a binary format, requiring <i>sar</i> itself for interpretation.<br>Historical data collection depends on a cron job or systemd timer, usually provided by the <b>sysstat</b> package. Without it, historical data won't be available.<br>Understanding the detailed metrics requires some system knowledge; outputs can be extensive.<br>Minimal overhead during data collection, but consider on highly loaded systems.


title: DATA PERSISTENCE
content:
<i>sar</i> historical data is typically stored in binary files named <i>saDD</i> (e.g., <i>sa01</i> for the 1st of the month) within <i>/var/log/sysstat/</i>. These files are managed by <b>logrotate</b> or similar services.<br>To view data from a specific date, use the <b>-f</b> option, for example: <b>sar -f /var/log/sysstat/sa15</b>.


title: REAL-TIME VS. HISTORICAL REPORTING
content:
When <i>interval</i> and <i>count</i> are provided (e.g., <b>sar -u 1 5</b>), <i>sar</i> reports real-time data directly from the kernel.<br>When only options like <b>-f</b>, <b>-s</b>, or <b>-e</b> are used without <i>interval</i> and <i>count</i>, <i>sar</i> reads and analyzes previously collected historical data from log files.


title: HISTORY
content:
<i>sar</i> is a core component of the <b>sysstat</b> package, tracing its origins back to <b>System V</b> Unix. It has served as a fundamental tool for system administrators for decades. The <b>sysstat</b> project, which maintains and extends <i>sar</i> and related utilities (like <b>iostat</b>, <b>mpstat</b>, <b>pidstat</b>), has been actively developed for Linux by Sebastien Godard since the late 1990s. Its continuous evolution and widespread adoption underscore its lasting importance in Linux performance monitoring.


title: PARAMETERS
content:
<b>-A</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Reports all activities currently available. This is equivalent to specifying all available options.<br><br><b>-b</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Reports I/O and transfer rate statistics.<br><br><b>-B</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Reports paging statistics.<br><br><b>-d</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Reports activity for each block device (e.g., disk I/O).<br><br><b>-f <filename></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Reads data from the specified <i>filename</i>. This is used for historical data analysis.<br><br><b>-H</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Reports hugepages utilization statistics.<br><br><b>-n {keyword}</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Reports network statistics. Common <i>keywords</i> include <b>DEV</b> (interface statistics), <b>EDEV</b> (error statistics), <b>SOCK</b> (sockets), <b>IP</b>, <b>TCP</b>, <b>UDP</b>, etc.<br><br><b>-o <filename></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Saves the collected data in binary format to the specified <i>filename</i>.<br><br><b>-q</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Reports queue length and load averages.<br><br><b>-r</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Reports memory utilization statistics (e.g., used, free, buffers, cached).<br><br><b>-u</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Reports CPU utilization. This is the default activity reported if no option is specified.<br><br><b>-v</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Reports inode, file, and other kernel tables statistics.<br><br><b>-w</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Reports task creation and context switching statistics.<br><br><b>-W</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Reports swap statistics (e.g., pages swapped in/out).<br><br><b>interval</b><br>&nbsp;&nbsp;&nbsp;&nbsp;The time in seconds between each report.<br><br><b>count</b><br>&nbsp;&nbsp;&nbsp;&nbsp;The number of reports to display. If not specified, <b>sar</b> reports continuously.<br><br>


title: DESCRIPTION
content:
The <b>sar</b> (System Activity Reporter) command, part of the <i>sysstat</i> package, is a powerful utility for collecting, reporting, and saving system activity information. It is indispensable for system administrators to monitor performance, identify bottlenecks, and troubleshoot issues.<br><br><b>sar</b> gathers data on various system resources such as CPU utilization, memory usage, I/O activity, network statistics, process creation, and more. It provides both real-time insights and the capability for historical data analysis. Its high configurability allows users to specify sampling intervals and the number of samples, or to read from previously saved data files, making it a versatile tool for comprehensive system performance analysis on Linux and Unix-like operating systems.


title: CAVEATS
content:
Using <b>sar</b> effectively requires the <i>sysstat</i> package to be installed on the system.<br><br>Interpreting the vast amount of data <b>sar</b> provides requires a good understanding of system metrics and performance indicators. While powerful, collecting data at very small intervals (e.g., less than 1 second) can introduce a slight overhead, especially on systems already under heavy load. Historical data logging and rotation are typically managed by <i>cron</i> jobs invoking the associated <b>sa1</b> and <b>sa2</b> scripts.


title: REAL-TIME MONITORING
content:
<b>sar</b> can be used for immediate, real-time performance monitoring. For example, <code>sar -u 1 5</code> will display CPU utilization every 1 second for 5 times, providing a quick snapshot of current system activity.


title: HISTORICAL DATA ANALYSIS
content:
By default on many distributions, <b>sar</b> logs daily activity data to files (typically in <i>/var/log/sysstat/</i> or <i>/var/log/sa/</i> directories, named <i>saXX</i> where <i>XX</i> is the day of the month). This historical data can be viewed using the <code>-f</code> option (e.g., <code>sar -f /var/log/sysstat/sa01</code>), enabling post-mortem analysis of performance trends and issues over time.


title: HISTORY
content:
<b>sar</b> is a fundamental utility within the <i>sysstat</i> project, which has been under continuous development for Linux since the late 1990s. It originated from similar system monitoring tools found in proprietary Unix systems. Over time, it has evolved into a robust and indispensable tool for system performance analysis and capacity planning across various Linux distributions.


title: SYNOPSIS
content:
<b>sass</b> <I>input_path</I> [<I>output_path</I>] [<I>options</I>]<br><b>sass</b> --watch <I>input_path</I>[:<I>output_path</I>] [<I>options</I>]<br><b>sass</b> --update <I>input_path</I>[:<I>output_path</I>] [<I>options</I>]


title: PARAMETERS
content:
<b>-w, --watch</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Watch source files for changes and recompile automatically.<br><br><b>-u, --update</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Compile only if the source file has been modified since the last compilation.<br><br><b>--style <name></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specify the output CSS style (e.g., <b>expanded</b>, <b>compressed</b>). The default is <b>expanded</b>.<br><br><b>--load-path <path></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specify a path to find imported Sass files. Can be used multiple times.<br><br><b>--no-source-map</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Do not generate a source map file for the compiled CSS.<br><br><b>--source-map-urls <type></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies how source map URLs are generated (<b>absolute</b> or <b>relative</b>).<br><br><b>--error-css</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Generate CSS even when errors occur, embedding the error message in the output.<br><br><b>-I, --indented-syntax</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Treat <i>*.sass</i> files as using the indented (original) Sass syntax rather than SCSS.<br><br><b>-h, --help</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Display help information about the command and its options.<br><br><b>-v, --version</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Display the version information of the Sass compiler.<br><br>


title: DESCRIPTION
content:
<i>Sass</i> (Syntactically Awesome Stylesheets) is a powerful CSS preprocessor scripting language that is interpreted or compiled into CSS. It enhances the capabilities of standard CSS by introducing features like variables, nested rules, mixins, functions, and partials. These features enable developers to write more maintainable, reusable, and efficient stylesheets.<br>By using Sass, you can organize your CSS code more effectively, reduce repetition, and streamline development workflows, especially in large-scale projects. While not a native Linux command, the Sass compiler is widely used on Linux systems as a command-line tool, transforming <i>.scss</i> or <i>.sass</i> files into standard <i>.css</i> files that web browsers can understand. It helps in creating modular and scalable front-end architectures.


title: CAVEATS
content:
<i>Sass</i> files (<i>.scss</i> or <i>.sass</i>) must be compiled into standard <i>.css</i> before they can be used by web browsers. This command-line tool serves as the compiler. It is not a built-in Linux utility but rather a development tool that needs to be installed, typically via a package manager like npm (for Dart Sass) or RubyGems (for Ruby Sass, now deprecated in favor of Dart Sass). Ensure you have a compatible runtime environment (Node.js or Ruby) if installing via their respective package managers.


title: USAGE WITH DIRECTORIES
content:
To compile all Sass files in a directory and output them to another directory, you can use the <code>--watch</code> flag with directory paths:<br><code><b>sass</b> --watch <I>input_directory</I>:<I>output_directory</I></code><br>This command will monitor changes in the input directory and recompile all modified Sass files, outputting them to the specified output directory with their original relative paths preserved.


title: OUTPUT STYLES
content:
The <code>--style</code> option allows you to control the formatting of the compiled CSS:<br><ul><li><b>expanded</b>: The default, human-readable CSS with standard indentation and line breaks.</li><li><b>compressed</b>: Minified CSS with all unnecessary whitespace removed, making the file size as small as possible.</li><li><b>nested</b>: (Deprecated in Dart Sass) Indented based on CSS nesting.</li><li><b>compact</b>: (Deprecated in Dart Sass) Each CSS rule is placed on a single line.</li></ul>


title: IMPORTING FILES
content:
Sass allows importing other Sass files using the <code>@import</code> rule. Files prefixed with an underscore (e.g., <i>_variables.scss</i>, <i>_mixins.sass</i>) are treated as "partials." Partials are not compiled into standalone CSS files; they are meant to be imported into other Sass files to modularize your stylesheets without creating unnecessary output files.


title: HISTORY
content:
<i>Sass</i> was initially designed and developed by Hampton Catlin in 2006 and was later extended by Natalie Weizenbaum and Chris Eppstein. The original implementation, often referred to as "Ruby Sass," used the Ruby programming language. Over time, the primary implementation shifted to "Dart Sass" (or "LibSass" via C++), which is now the recommended and most actively maintained version, offering faster compilation and easier installation in many environments. Its widespread adoption significantly influenced modern web development workflows by promoting modularity and maintainability in stylesheets.


title: SYNOPSIS
content:
<b>satis</b> <I>[command]</I> <I>[options]</I> <I>[arguments]</I><br><br>Common commands include:<br><b>satis build</b> <I>[--repository-url=<url>]</I> <I>[--packages=<package1,package2>]</I> <I>[options]</I><br><b>satis init</b> <I>[options]</I><br><b>satis validate</b> <I>[options]</I>


title: PARAMETERS
content:
<b><b>build</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Generates the static Composer repository based on the <i>satis.json</i> configuration file. This is the most frequently used command.<br><br><b><b>init</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Initializes a basic <i>satis.json</i> configuration file in the current directory, providing a starting point for your repository.<br><br><b><b>validate</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Checks the <i>satis.json</i> configuration file for syntax errors and common issues without building the repository.<br><br><b><b>--no-interaction</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Prevents <b>satis</b> from asking any interactive questions during execution, useful for automated scripts.<br><br><b><b>-v</b>, <b>-vv</b>, <b>-vvv</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Increases the verbosity of messages: <b>-v</b> for normal output, <b>-vv</b> for more verbose, and <b>-vvv</b> for debug output.<br><br><b><b>--ansi</b> / <b>--no-ansi</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Forces or disables ANSI output (colored output) for the command line.<br><br><b><b>--profile</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays timing and memory usage information after the command execution.<br><br>


title: DESCRIPTION
content:
<i>Satis</i> is a command-line tool built on top of <b>Composer</b> that serves as a static Composer repository generator. It allows you to create a local, self-hosted mirror of your PHP project dependencies, including both public packages from Packagist and private packages from your own Git or other version control systems.<br><br>The primary use case for <b>satis</b> is to provide a reliable, fast, and private source for your Composer dependencies. Instead of fetching packages directly from external sources like Packagist.org for every deployment, you can point your projects to your internally generated <b>satis</b> repository. This is particularly beneficial for large organizations, CI/CD pipelines, or when dealing with numerous private packages.<br><br>When run, <b>satis</b> reads a configuration file (typically <i>satis.json</i>) that specifies which packages and repositories it should mirror. It then fetches these packages, resolves their dependencies, and generates a set of static JSON and package files, often placed in a "web" directory. This directory can then be served by any standard web server (e.g., Nginx, Apache) to act as a Composer repository.


title: CAVEATS
content:
<i>Satis</i> requires <b>PHP</b> and <b>Composer</b> to be installed and accessible. Building large repositories can consume significant disk space and take a considerable amount of time, especially during the initial build or when many packages are updated. It's crucial to ensure the generated "web" directory is served securely if it contains private packages or sensitive information. <b>satis</b> is a repository generator, not a package manager itself; it relies on <b>Composer</b> for dependency resolution and installation.


title: CONFIGURATION FILE (<I>SATIS.JSON</I>)
content:
The core of <b>satis</b> operation relies on a JSON configuration file, typically named <i>satis.json</i>. This file defines the `homepage` for your repository, a list of `repositories` (e.g., Git, VCS, Packagist) to source packages from, and a `require` section specifying which packages from those repositories should be mirrored. It also supports `archive` options for creating zipped package archives and `config` settings.


title: GENERATED OUTPUT
content:
Upon successful execution of the <b>build</b> command, <b>satis</b> generates a directory (defaulting to 'web/') containing static JSON files (e.g., `packages.json`, `p/provider-2016-1.json`) and potentially zipped archives of packages. This output directory is designed to be served directly by any static file server, making it a ready-to-use Composer repository.


title: HISTORY
content:
<i>Satis</i> was developed by the creators of <b>Composer</b>, Nils Adermann and Jordi Boggiano, as a complementary tool to address the need for self-hosted Composer repositories. It emerged to provide a solution for private package hosting and to reduce reliance on external services like Packagist.org for internal or large-scale deployments, thereby improving build speeds and reliability within controlled environments.


title: PARAMETERS
content:
<b><b>-j</b> <i>&lt;jobid&gt;</i>[.<i>&lt;stepid&gt;</i>], <b>--jobid=</b><i>&lt;jobid&gt;</i>[.<i>&lt;stepid&gt;</i>]</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specify the Slurm job ID and optionally the job step ID to which to attach. This is the primary argument for identifying the target.<br><br><b><b>-l</b>, <b>--label</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Prepend all lines of output from the attached job or step with its job ID and step ID for easier identification.<br><br><b><b>-s</b>, <b>--slim</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Suppress initial informational headers printed by <i>sattach</i>, outputting only the attached job's data.<br><br><b><b>-x</b>, <b>--exit-on-eof</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Exit <i>sattach</i> when an End-of-File (EOF) is received on any of the standard I/O streams (stdin, stdout, stderr) from the attached job.<br><br><b><b>-q</b>, <b>--quiet</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Do not print informational messages; only display the job's output.<br><br><b><b>-p</b>, <b>--pty</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Request a pseudo-terminal (PTY) allocation for the attached job. This is essential for proper interaction with shell-based or interactive applications.<br><br><b><b>-d</b>, <b>--detach</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Do not send a SIGHUP signal to the attached job or step upon <i>sattach</i> exit. This ensures the job continues running unaffected when <i>sattach</i> terminates.<br><br><b><b>--clear-input</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Clear the existing input buffer for the job step before attaching to its standard input, preventing stale input from being processed.<br><br><b><b>--timeout=</b><i>&lt;seconds&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specify the maximum time in seconds to wait for the job step to be ready for attachment. If the timeout is exceeded, <i>sattach</i> will fail.<br><br><b><b>--verbose</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Increase the verbosity of <i>sattach</i>'s output, showing more detailed diagnostic or informational messages.<br><br><b><b>--version</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Display the <i>sattach</i> version number and exit.<br><br><b><b>--help</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Display a brief help message summarizing command usage and options, then exit.<br><br>


title: DESCRIPTION
content:
<i>sattach</i> is a utility within the <b>Slurm Workload Manager</b> suite designed to connect to the standard input, output, and error streams of an already running job step on a compute node.<br><br>This command allows users to observe a job's real-time output, or provide input if the job is interactive, without directly logging into the execution node. It's particularly useful for debugging long-running processes, monitoring progress, or re-establishing a connection to interactive shell sessions launched via <i>srun</i> that may have become detached. <i>sattach</i> requires the job ID and optionally the job step ID to establish the connection, providing a non-intrusive way to interact with distributed jobs.


title: CAVEATS
content:
<i>sattach</i> is part of the <b>Slurm Workload Manager</b> and requires a functional Slurm environment. Users can typically only attach to job steps they own due to security considerations. Attempting to attach to a job's standard input when it's not designed for interactive input or expects input from a file can lead to unexpected behavior or interfere with the job's execution.


title: USAGE CONTEXT
content:
<i>sattach</i> is primarily utilized in <b>High-Performance Computing (HPC) environments</b> where Slurm is deployed as the resource manager. It is invaluable for system administrators and researchers who need to interact with or monitor the progress of specific job steps or interactive sessions launched via <i>srun</i> without direct node login.


title: PERMISSIONS AND SECURITY
content:
By default, a user is restricted to attaching only to their own job steps. However, system administrators can configure Slurm (e.g., via the <i>AllowAttach</i> parameter in <i>slurm.conf</i>) to permit other users or groups, such as support staff, to attach to jobs for collaborative debugging or operational support purposes.


title: HISTORY
content:
<i>sattach</i> is an integral component of the <b>Slurm Workload Manager</b>, which originated in the early 2000s (around 2002-2003) as a robust, open-source job scheduler for HPC clusters. Its functionality has evolved alongside Slurm, providing a critical tool for real-time monitoring, debugging, and interaction with jobs running in distributed environments, addressing the complex needs of modern cluster management.


title: SYNOPSIS
content:
<i>savelog</i> [OPTIONS] <LOG_FILE...><br>The command processes one or more log files, typically by archiving, compressing, or rotating them based on the specified options.


title: PARAMETERS
content:
<b><i>-c</i>, <i>--compress</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Compress the archived log file, typically using <i>gzip</i>.<br><br><b><i>-t</i>, <i>--timestamp</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Append a timestamp (e.g., YYYYMMDD) to the archived log filename.<br><br><b><i>-d</i>, <i>--destination</i> <i>DIR</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specify the target directory for archived log files. Defaults to the source file's directory.<br><br><b><i>-k</i>, <i>--keep</i> <i>N</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Retain only the last <i>N</i> archived log files, deleting older ones.<br><br><b><i>-v</i>, <i>--verbose</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Enable verbose output, showing details of operations performed.<br><br>


title: DESCRIPTION
content:
<i>savelog</i> is a utility designed to manage and archive log files, typically employed by system administrators or custom applications. It automates the process of moving current log data into historical archives, often applying compression and timestamping. This prevents individual log files from growing indefinitely, consuming excessive disk space, and making log analysis difficult. While not a standard command across all Linux distributions, its functionality often mimics parts of <i>logrotate</i> or simpler archiving scripts. It ensures that critical historical data is preserved while keeping active logs manageable for real-time monitoring and troubleshooting. It might handle single files or directories, depending on its specific implementation, often leveraging standard archiving tools like <i>tar</i> or <i>gzip</i> internally.


title: CAVEATS
content:
The <i>savelog</i> command is <b>not a standard Linux utility</b> found in most distributions. It commonly refers to custom scripts or functions designed for specific system setups or applications. Its exact behavior, options, and availability will vary greatly depending on its particular implementation. Users seeking general log management solutions should refer to standard tools like <i>logrotate</i> or <i>logsave</i>.


title: HISTORY
content:
Given that <i>savelog</i> is not a standard, universally distributed command, it does not have a formal, documented history of development and usage like commands such as <i>ls</i> or <i>grep</i>. Its origin typically lies in ad-hoc scripting by system administrators or developers who created simple utilities to manage application-specific log files before or alongside more comprehensive solutions like <i>logrotate</i> became widely adopted or configured. It represents a common task implemented in a bespoke manner.


title: SYNOPSIS
content:
<br><b>sbatch</b> [<i>OPTIONS</i>] <i>&lt;script_name&gt;</i> [<i>&lt;script_arguments&gt;</i>]<br><b>sbatch</b> [<i>OPTIONS</i>] <i>--wrap="&lt;command_string&gt;"</i>


title: PARAMETERS
content:
<b>--account, -A</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Charge resources used by this job to <I>account</I>.<br><br><b>--array=<indexes></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Submit a job array with task IDs specified by <I>indexes</I> (e.g., 0-9, 1,3,5).<br><br><b>--chdir, -D <directory></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Set the working directory of the batch script to <I>directory</I>.<br><br><b>--cpus-per-task, -c <count></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Request <I>count</I> CPUs per task.<br><br><b>--constraint, -C <features></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Request nodes with specific <I>features</I> (e.g., 'GPU&K20').<br><br><b>--dependency, -d <dependency_list></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Defer the start of this job until <I>dependency_list</I> (e.g., 'afterok:1234') is satisfied.<br><br><b>--error, -e <filepath></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Redirect stderr to <I>filepath</I>. Formats like <I>%j</I> (job ID) can be used.<br><br><b>--export=<vars></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Control which environment variables are exported to the job. Common values: <I>ALL</I>, <I>NONE</I>, <I>VAR1,VAR2</I>.<br><br><b>--exclusive</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Allocate nodes exclusively to this job.<br><br><b>--job-name, -J <name></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specify a <I>name</I> for the job.<br><br><b>--mail-type=<type></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Notify user by email when <I>type</I> of event occurs (e.g., <I>BEGIN</I>, <I>END</I>, <I>FAIL</I>, <I>ALL</I>).<br><br><b>--mail-user=<email_address></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Send email notifications to <I>email_address</I>.<br><br><b>--mem=<size></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Request <I>memory</I> (e.g., 10G for 10 Gigabytes) per node or per CPU. Suffixes like <I>M</I>, <I>G</I>, <I>T</I> are supported.<br><br><b>--nodes, -N <min_nodes[-max_nodes]></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Request <I>min_nodes</I>[-<I>max_nodes</I>] to be allocated for the job.<br><br><b>--ntasks, -n <count></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Request <I>count</I> tasks for the job.<br><br><b>--output, -o <filepath></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Redirect stdout to <I>filepath</I>. Formats like <I>%j</I> (job ID) can be used.<br><br><b>--partition, -p <partition_name></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Request a specific <I>partition</I> (queue) for the job.<br><br><b>--time=<time></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Set a time limit for the job execution, e.g., <I>DD-HH:MM:SS</I>, <I>HH:MM:SS</I>, <I>MM</I>.<br><br><b>--wrap="<command_string>"</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Submit the <I>command_string</I> as a job, bypassing the need for a script file.<br><br><b>--wait</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Block until the submitted job completes.<br><br>


title: DESCRIPTION
content:
<br>The <b>sbatch</b> command is a fundamental utility within the Slurm Workload Manager, designed to submit a job script for asynchronous execution on a cluster. It serves as the primary mechanism for users to convey their computational tasks and their resource requirements—such as CPU cores, memory, time limits, and specific nodes—to the Slurm scheduler. Unlike <b>srun</b>, which is used for interactive or synchronous job execution, <b>sbatch</b> queues jobs to run non-interactively when the requested resources become available. This makes it an indispensable tool for long-running, high-throughput computing, and scientific simulations that do not require immediate user interaction. A typical <b>sbatch</b> job involves creating a shell script containing the commands to be executed, often prefaced with special <i>#SBATCH</i> directives that instruct Slurm on various job parameters like partition, output files, and dependencies.


title: CAVEATS
content:
Job parameters specified on the command line override those specified in <i>#SBATCH</i> directives within the script.<br><b>sbatch</b> only submits the job; it does not execute the job script directly or immediately.<br>Jobs may queue for extended periods depending on available resources and cluster policy.<br>It is not suitable for interactive sessions; use <b>srun</b> for such purposes.


title: <I>#SBATCH</I> DIRECTIVES
content:
Job scripts often begin with lines like <i>#SBATCH --nodes=1</i> or <i>#SBATCH --time=01:00:00</i>. These directives provide a way to specify job parameters directly within the script file, making scripts self-contained and reproducible. <b>sbatch</b> parses these lines and applies the requested resources. Command-line options take precedence over these directives.


title: JOB SUBMISSION OUTPUT
content:
Upon successful submission, <b>sbatch</b> prints a job ID to standard output, typically in the format <i>Submitted batch job &lt;JOB_ID&gt;</i>. This ID is crucial for monitoring, cancelling, or querying the job's status using other Slurm commands like <b>squeue</b> or <b>scancel</b>.


title: HISTORY
content:
Slurm, and by extension <b>sbatch</b>, emerged as a modern, open-source workload manager to address the evolving needs of high-performance computing clusters. It was developed to replace older systems like PBS Pro and Torque, offering improved scalability, flexibility, and features for managing complex computational workflows. <b>sbatch</b> has been a core component since Slurm's inception, providing the standard mechanism for users to submit batch jobs to the cluster. Its design reflects the common requirement in HPC environments to queue and execute non-interactive tasks efficiently.


title: SYNOPSIS
content:
<b>sbcast</b> [<i>OPTIONS</i>] <i>&lt;source_file&gt; &lt;destination_file&gt;</i><br><b>sbcast</b> <i>-L</i><br><i><br>Examples:</i><br><b>sbcast</b> <i>-f --preserve /path/to/my_executable /tmp/my_executable_local</i><br><b>sbcast</b> <i>--compress my_large_data.txt /scratch/local/data.txt</i>


title: PARAMETERS
content:
<b><b>-L, --list</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Lists the valid nodes for the current job that <b>sbcast</b> can target. This option does not perform a file transfer.<br><br><b><b>-f, --force</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Overwrites the destination file if it already exists on the target nodes.<br><br><b><b>-p, --preserve</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Preserves the original file's permissions, ownership, and modification timestamps on the destination nodes.<br><br><b><b>-v, --verbose</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Increases the verbosity of the output, providing more information about the transfer process.<br><br><b><b>-d, --debug</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets the logging level to debug, providing very detailed output for troubleshooting.<br><br><b><b>-q, --quiet</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Suppresses all informational and warning messages, displaying only errors.<br><br><b><b>-m, --mode=&lt;permissions&gt;</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets the permissions for the destination file using an octal representation (e.g., <i>0644</i>).<br><br><b><b>--compress[=level]</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Compresses the file during transfer to reduce network bandwidth usage. An optional compression level (1-9) can be specified, with 1 being fastest and 9 being best compression.<br><br><b><b>--remote-path=&lt;path&gt;</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;(Slurm 23.02+) Specifies an alternative destination path on the remote nodes. The <i>&lt;destination_file&gt;</i> argument then becomes just the filename, not the full path.<br><br><b><b>--help</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays a help message and exits.<br><br><b><b>--version</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Shows version information and exits.<br><br>


title: DESCRIPTION
content:
<b>sbcast</b> is a specialized command-line utility provided as part of the <b>Slurm Workload Manager</b>. Its primary function is to efficiently broadcast a single file from the launching host to all allocated compute nodes within an active Slurm job. Unlike traditional file transfer methods like <b>scp</b> or shared file systems, <b>sbcast</b> leverages a tree-based communication algorithm to distribute the file, significantly reducing network congestion and load on shared file systems, especially in large-scale parallel computing environments. This makes it ideal for scenarios where a large executable, input data file, or library needs to be quickly and uniformly distributed to hundreds or thousands of compute nodes running a parallel application. By using <b>sbcast</b>, users can avoid I/O bottlenecks that commonly arise when many processes simultaneously try to read the same file from a network file system. It ensures that each compute node receives a local copy of the specified file, optimizing application startup and execution performance.


title: CAVEATS
content:
<b>sbcast</b> is designed exclusively for use within an active <b>Slurm</b> job allocation. It cannot be used to transfer files to arbitrary hosts or outside of a <b>Slurm</b> job context. The functionality of <b>sbcast</b> depends on the <b>sbcast</b> plugin being properly configured and enabled in the <b>Slurm</b> installation on the cluster. It is most beneficial for transferring large files to a significant number of nodes, where traditional methods might suffer from I/O contention. For small files or single-node transfers, its overhead might not provide a significant advantage.


title: USAGE CONTEXT
content:
<b>sbcast</b> must be executed from within an active <b>Slurm</b> job allocation. This means you typically run it either directly from an <b>srun</b> interactive session or as a command inside an <b>sbatch</b> script after resources have been allocated. It leverages <b>Slurm</b>'s internal communication mechanisms to target the specific nodes assigned to your job.


title: PERFORMANCE ADVANTAGES
content:
The core strength of <b>sbcast</b> lies in its use of a tree-based broadcasting algorithm. Instead of each node fetching the file independently from a central source, <b>sbcast</b> arranges the transfers in a hierarchical, fan-out manner. This significantly reduces the load on the source and network, making it highly efficient for distributing large files to a vast number of compute nodes simultaneously, thereby accelerating job startup and overall execution.


title: SLURM PLUGIN REQUIREMENT
content:
For <b>sbcast</b> to function, the <b>sbcast</b> plugin must be enabled and configured within the <b>Slurm</b> installation on your cluster. If this plugin is not present or enabled, the <b>sbcast</b> command will not work, or it will report an error.


title: HISTORY
content:
<b>sbcast</b> emerged as a critical component of the <b>Slurm Workload Manager</b> to address a common bottleneck in large-scale high-performance computing (HPC) environments: efficient distribution of files to hundreds or thousands of compute nodes. Traditional shared file systems often become I/O contention points when numerous parallel processes attempt to access the same file concurrently. <b>sbcast</b> was developed to mitigate this by implementing a specialized tree-based broadcast algorithm, allowing files to be distributed rapidly and with minimal load on the central file servers. Its integration into <b>Slurm</b> underscores the system's commitment to optimizing performance for parallel applications by providing low-latency, high-bandwidth file distribution directly within the job allocation. It became increasingly important as cluster sizes grew and applications became more I/O intensive.


title: PARAMETERS
content:
<b><b>--version</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Prints SBCL's version string and exits.<br><br><b><b>--help</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Prints a summary of command line options and exits.<br><br><b><b>--core</b> <i>&lt;file&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Uses the specified core file instead of the default <i>sbcl.core</i>. A core file contains the Lisp runtime environment and often preloaded libraries.<br><br><b><b>--no-userinit</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Prevents loading the user's <i>~/.sbclrc</i> initialization file, which typically contains user-specific Lisp configurations.<br><br><b><b>--no-sysinit</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Prevents loading the system's <i>sbclrc</i> initialization file, often located in <i>/etc/sbclrc</i> or similar paths.<br><br><b><b>--disable-debugger</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Disables the debugger. When an error occurs, SBCL will exit immediately instead of entering the debugger, which can be useful for automated scripts.<br><br><b><b>--dynamic-space-size</b> <i>&lt;megabytes&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets the initial size of the dynamic memory space (heap) for Lisp objects in megabytes. This space is managed by the garbage collector.<br><br><b><b>--control-stack-size</b> <i>&lt;megabytes&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets the size of the control stack in megabytes. This stack is used for function calls and local variables.<br><br><b><b>--without-threads</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Runs SBCL without multi-threading support. This option is only effective if SBCL was built with optional thread support and is useful for specific debugging or deployment scenarios.<br><br><b><b>--end-runtime-options</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Marks the end of SBCL's command-line options. Any subsequent arguments are passed directly to the Lisp program and can be accessed via the <i>*posix-argv*</i> variable.<br><br><b><b>--non-interactive</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Does not enter the interactive REPL (Read-Eval-Print Loop) after processing other options. SBCL will exit after executing any specified <b>--load</b> or <b>--eval</b> forms.<br><br><b><b>--quit</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Exits SBCL after processing all other command-line options and any loaded/evaluated Lisp code. Often used in conjunction with <b>--eval</b> or <b>--load</b> for one-off tasks.<br><br><b><b>--eval</b> <i>&lt;form&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Evaluates the given Lisp form. This option can be used multiple times; forms are evaluated sequentially in the order they appear on the command line.<br><br><b><b>--load</b> <i>&lt;file&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Loads and executes the specified Lisp file. This option can be used multiple times; files are loaded sequentially in the order they appear.<br><br><b><b>--script</b> <i>&lt;file&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Loads the specified Lisp file and then exits, similar to <b>--load</b> combined with <b>--quit</b> and <b>--non-interactive</b>. All subsequent command-line arguments are passed to the Lisp program via <i>*posix-argv*</i>, making it ideal for creating executable Lisp scripts (e.g., using a shebang line).<br><br><b><b>--sysinit</b> <i>&lt;file&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Loads the specified system-wide initialization file instead of the default system <i>sbclrc</i>.<br><br><b><b>--userinit</b> <i>&lt;file&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Loads the specified user initialization file instead of <i>~/.sbclrc</i>.<br><br>


title: DESCRIPTION
content:
<i>SBCL</i> (Steel Bank Common Lisp) is an open-source, high-performance Common Lisp implementation widely used in the Lisp community. It is renowned for its optimizing native code compiler, which translates Lisp code directly into machine code for various architectures, resulting in fast execution. SBCL provides a comprehensive interactive development environment (REPL - Read-Eval-Print Loop), a powerful debugger, and a robust foreign function interface (FFI) for interoperability with C and other languages.<br><br>Adhering strictly to the ANSI Common Lisp standard, SBCL offers multi-threading support, a powerful object system (CLOS), and extensive libraries. Its stability, performance, and rich feature set make it a reliable choice for diverse applications, ranging from scripting and prototyping to complex systems and scientific computing.


title: CAVEATS
content:
<b>Memory Usage</b>: Lisp images can consume significant memory, especially for larger applications, due to garbage collection and the runtime environment. Users should be mindful of the dynamic space size configuration.<br><br><b>Startup Time</b>: While highly optimized, the startup time for SBCL can be slightly noticeable for very small, frequently executed scripts compared to shell scripts or other compiled languages, due to the loading of the Lisp image.<br><br><b>Lisp Learning Curve</b>: Common Lisp itself, upon which SBCL is built, has a significant learning curve, especially for developers unfamiliar with its syntax, paradigms (e.g., macros, CLOS), and dynamic nature. This is a general ecosystem consideration, not specific to SBCL's implementation quality.


title: REPL (READ-EVAL-PRINT LOOP)
content:
SBCL's interactive <i>REPL</i> is fundamental to Common Lisp development. It allows users to experiment with code, inspect objects, and debug programs incrementally in a dynamic and interactive environment, promoting rapid prototyping and exploration.


title: FOREIGN FUNCTION INTERFACE (FFI)
content:
SBCL includes a powerful <i>FFI</i> that allows Lisp code to seamlessly call functions in shared libraries written in C, C++, or other languages, and vice versa. This enables robust integration with existing system libraries and external components, extending Lisp's capabilities.


title: IMAGE DUMPING
content:
SBCL can 'dump' its current state, including loaded code, compiled functions, and data, into an executable core file. This feature is crucial for creating standalone Lisp applications or quickly restarting complex Lisp environments without reloading all components from scratch, significantly reducing startup time for large systems.


title: HISTORY
content:
<i>SBCL</i> originated in 1999 as a fork of <i>CMUCL</i> (Carnegie Mellon University Common Lisp), which was developed at CMU in the late 1980s. The primary motivation for the fork was to establish a stable, high-performance, and strictly ANSI Common Lisp compliant implementation, diverging from CMUCL's more experimental nature. Over the years, SBCL has become one of the most widely used and respected Common Lisp implementations, recognized for its robust native code compiler, multi-threading capabilities, and strong adherence to the Common Lisp standard. It continues to be actively developed and maintained by a dedicated community of volunteers.


title: PARAMETERS
content:
<b><b>-h</b>, <b>--help</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays a help message and exits.<br><br><b><b>-mem</b> <I>&lt;size&gt;</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets the maximum JVM heap size for <i>sbt</i> (e.g., <b>-mem 2048</b> for 2GB).<br><br><b><b>-debug</b>, <b>-trace</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Enables verbose debugging or stack tracing output.<br><br><b><b>-sbt-version</b> <I>&lt;version&gt;</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies a particular <i>sbt</i> version to use for the project.<br><br><b><b>-sbt-dir</b> <I>&lt;directory&gt;</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the directory where <i>sbt</i> stores its global files and caches.<br><br><b><b>-no-share</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Disables sharing of project configuration and caches among projects.<br><br><b><b>-batch</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Runs <i>sbt</i> in non-interactive batch mode. Useful for scripting.<br><br><b><b>-no-colors</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Disables ANSI color output in the console.<br><br><b><b>-warn-fatal-warnings</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Treats all warnings as fatal errors, stopping the build.<br><br><b><b>-Dsbt.<property>=<value></b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Passes a system property to the JVM running <i>sbt</i> (e.g., <b>-Dsbt.log.format=false</b>).<br><br><b><b>--</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Separator indicating that subsequent arguments are commands or arguments to be passed to <i>sbt</i> itself, not launcher options.<br><br>


title: DESCRIPTION
content:
<i>sbt</i> (Simple Build Tool) is an open-source build tool primarily designed for Scala projects, offering robust support for Java as well. It provides features like fast incremental compilation, automated dependency management via Apache Ivy, and a powerful interactive shell. Developers use <i>sbt</i> to compile, test, run, and package their applications efficiently. Its configuration is handled through Scala-based build definition files (typically <b>build.sbt</b>), which allows for highly flexible and programmatic build logic. <i>sbt</i> aims to optimize the development workflow for JVM-based projects, especially those leveraging Scala's advanced language features.


title: CAVEATS
content:
Initial startup of <i>sbt</i> can be notably slow due to JVM spin-up and dependency resolution. It can also be memory-intensive, especially for large projects, requiring sufficient JVM heap allocation. The Scala-centric configuration (<b>build.sbt</b>) can present a learning curve for developers unfamiliar with Scala DSLs. Version compatibility between <i>sbt</i>, Scala, and plugins sometimes requires careful management.


title: INTERACTIVE MODE
content:
When invoked without specific commands, <i>sbt</i> enters an interactive shell. This mode provides a powerful REPL-like environment where developers can execute build commands, inspect settings, and get immediate feedback, significantly accelerating the development cycle.


title: BUILD DEFINITION (BUILD.SBT)
content:
Project configuration in <i>sbt</i> is primarily done through <b>build.sbt</b> files. These files are themselves Scala programs, allowing for highly expressive and programmatic control over the build process, including task definitions, dependency management, and project settings.


title: PLUGINS
content:
<i>sbt</i> features a rich and extensible plugin ecosystem. Plugins extend <i>sbt</i>'s core functionality, enabling integrations with various tools, facilitating common tasks like publishing artifacts, code generation, and deployment, and enhancing the overall build experience.


title: HISTORY
content:
<i>sbt</i> was originally created by Mark Harrah and first released around 2008. It rapidly became the de-facto standard build tool for Scala projects due to its strong integration with Scala's features, particularly incremental compilation. Early versions (0.7.x) used an XML-based configuration, but later releases (0.10+ onwards) transitioned to a more powerful and flexible Scala-based DSL (Domain Specific Language) for build definitions (<b>build.sbt</b>). This evolution cemented <i>sbt</i>'s role as a sophisticated and efficient build tool for the Scala ecosystem.


title: SYNOPSIS
content:
<b>sbuild</b> [<i>OPTIONS</i>] &lt;<i>source-package</i> | <i>.dsc file</i> | <i>.changes file</i>&gt;


title: PARAMETERS
content:
<b>-c, --chroot=CHROOT</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specify the <i>schroot</i> chroot name or path to use for building.<br><br><b>-d, --dist=DISTRIBUTION</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specify the distribution (e.g., 'sid', 'bookworm') to build for.<br><br><b>-A, --arch=ARCHITECTURE</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specify the architecture (e.g., 'amd64', 'arm64') for the build.<br><br><b>-h, --host=HOST_ARCHITECTURE</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specify the host architecture for cross-compilation builds.<br><br><b>-s, --source</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Only build the source package (<i>.dsc</i>, <i>.orig.tar.{gz|xz|bz2}</i>, <i>.debian.tar.{gz|xz|bz2}</i>).<br><br><b>-b, --build</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Only build the binary packages (<i>.deb</i> files).<br><br><b>--clean-chroot</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Clean the chroot (e.g., revert to snapshot) after the build (default).<br><br><b>--no-clean-chroot</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Do not clean the chroot after the build, useful for debugging.<br><br><b>--run-command=COMMAND</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Run an arbitrary command inside the chroot before the build.<br><br><b>--extra-dep=PACKAGE</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Add an extra build dependency to be installed in the chroot before building.<br><br><b>--force-orig-source</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Force the use of the original tarball even if a newer version is present.<br><br><b>--no-run-lintian</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Do not run <i>lintian</i> on the built packages.<br><br><b>-v, --verbose</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Enable verbose output during the build process.<br><br><b>-D, --debug</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Enable debug output.<br><br>


title: DESCRIPTION
content:
<i>sbuild</i> is a powerful command-line tool used for securely and reproducibly building Debian packages within an isolated environment, typically a <i>chroot</i> or container. It acts as a wrapper around package building utilities like <i>dpkg-buildpackage</i> or <i>debuild</i>, but crucially manages the build environment itself.<br><br>By performing builds in a clean, isolated chroot, <i>sbuild</i> ensures that all declared build dependencies are met and that no extraneous files from the host system interfere with the build. This practice is vital for achieving reproducible builds, enhancing security, and verifying that packages only rely on their specified dependencies. It commonly integrates with <i>schroot</i> to manage the chroot environments, providing a robust framework for official Debian package builds and local development.


title: CAVEATS
content:
Using <i>sbuild</i> requires pre-configured <i>schroot</i> environments (chroots). Setting up these chroots, including user mapping and package repositories, can be non-trivial and often involves tools like <i>debootstrap</i> and careful <i>schroot</i> configuration. Network access within the chroot is typically required for fetching build dependencies. Proper user permissions and groups must be set up for <i>sbuild</i> to function correctly.


title: CONFIGURATION FILES
content:
<i>sbuild</i> can be configured globally via <i>/etc/sbuild/sbuild.conf</i> and on a per-user basis using <i>~/.sbuildrc</i>. These files allow customization of default chroots, build options, and other behaviors.


title: CHROOT SETUP
content:
While <i>sbuild</i> orchestrates the build, the underlying chroot environments must be prepared separately. This typically involves using <i>debootstrap</i> to create a minimal Debian system and then configuring it as an <i>schroot</i> session.


title: HISTORY
content:
<i>sbuild</i> originated within the Debian project to provide a robust and secure method for building official Debian packages. It was developed to overcome the limitations of building directly on a host system, which could lead to non-reproducible builds due to varied environments. Its reliance on <i>schroot</i> for managing isolated build environments has been a cornerstone of its design, enabling consistent and clean build processes critical for the Debian archive. It has evolved significantly over time, adapting to new build requirements and chroot management practices.


title: PARAMETERS
content:
<b>-n</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Do not load the user's default configuration file, typically <i>~/.scimrc</i>, upon startup.<br><br><b>-s "<commands>"</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Execute a series of <b>sc-im</b> script commands passed as a string. Commands should be separated by semicolons.<br><br><b>-V</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Display the version number of <b>sc-im</b> and then exit.<br><br><b>-h</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Show a brief help message with available command-line options and then exit.<br><br><b>-u <file></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Load a specified configuration file instead of the default <i>~/.scimrc</i>. This allows for custom session settings.<br><br><b><file></b><br>&nbsp;&nbsp;&nbsp;&nbsp;The path to a spreadsheet file (e.g., CSV, TSV, or <b>sc</b> format) to open upon starting <b>sc-im</b>.<br><br>


title: DESCRIPTION
content:
<b>sc-im</b>, short for <i>spreadsheet calculator - improved</i>, is a free, curses-based spreadsheet program designed for the terminal. It is a modern re-implementation of the classic <b>sc</b> spreadsheet, significantly enhanced with powerful features and <i>vim</i>-like keybindings, making it ideal for command-line enthusiasts, developers, and system administrators. It supports complex formulas, CSV/TSV import and export, macro recording, scripting capabilities, and undo/redo functionality. Its minimalist, text-based interface allows for efficient data manipulation directly within a shell environment, leveraging familiar navigation and editing paradigms from <i>Vim</i>.


title: CAVEATS
content:
<b>sc-im</b> has a relatively steep learning curve for users unfamiliar with <i>vi</i> or <i>vim</i> keybindings, as its navigation and editing paradigms are heavily inspired by these text editors. Being a terminal-based application, it lacks the graphical presentation and visual tools common in GUI spreadsheets, which might make complex data visualization or mouse-driven interaction less intuitive.


title: SCRIPTING AND AUTOMATION
content:
<b>sc-im</b> supports a powerful scripting language, allowing users to automate complex tasks, perform batch operations, and integrate spreadsheet functionalities into larger shell scripts. This capability significantly enhances its utility for repetitive data processing or report generation.


title: MACRO RECORDING
content:
Users can record sequences of commands and actions as macros, which can then be replayed to quickly apply the same operations to different data sets or areas of the spreadsheet, boosting productivity for common workflows.


title: HISTORY
content:
<b>sc-im</b> emerged as an improved and modernized fork of the original <b>sc</b> (spreadsheet calculator) program, which was a classic terminal-based spreadsheet. The development of <b>sc-im</b> aimed to integrate modern features, such as enhanced scripting, undo/redo, and more robust file handling, while adopting the efficient and powerful <i>vim</i>-like keybindings that are popular among command-line users. This evolution has made <b>sc-im</b> a more versatile and user-friendly tool for spreadsheet management in a console environment.


title: SYNOPSIS
content:
<b>sc_analysis_dump</b> [-d <i>&lt;directory&gt;</i> | -o <i>&lt;file&gt;</i>] [-t <i>&lt;startTime&gt;</i>:<i>&lt;endTime&gt;</i>] [-x <i>&lt;dumpOption&gt;</i>] [-f] [-v]


title: PARAMETERS
content:
<b>-d <i>&lt;directory&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the directory where `sc_analysis` collected the analysis data to be dumped from. This is often an internal data repository.<br><br><b>-o <i>&lt;file&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the output file where the dumped analysis data will be written. Note that typically only one of `-d` (source) or `-o` (destination) is used to define the primary operation context.<br><br><b>-t <i>&lt;startTime&gt;</i>:<i>&lt;endTime&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Defines a specific time range for the data to be dumped. Times are usually specified in Unix epoch format or a specific system-defined timestamp format like YYYYMMDD.HHMMSS.<br><br><b>-x <i>&lt;dumpOption&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the type of data to dump. Common options include <i>all</i> (for comprehensive data), <i>summary</i>, <i>io</i>, <i>latency</i>, <i>stats</i>, <i>events</i>, <i>fileset</i>, or <i>inode</i>, allowing for targeted data extraction based on diagnostic needs.<br><br><b>-f</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Forces the dump operation, potentially overriding warnings or existing files without prompting for confirmation.<br><br><b>-v</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Enables verbose output, providing more detailed information about the dump process, which can be useful for debugging the command itself.<br><br>


title: DESCRIPTION
content:
The `sc_analysis_dump` command is a utility within the <b>IBM Spectrum Scale</b> (formerly GPFS) file system suite. Its primary function is to <i>extract and dump</i> previously collected performance and diagnostic data, which was gathered by the `sc_analysis` command. This data is crucial for in-depth problem determination, performance analysis, and often used by IBM support for advanced diagnostics. It allows administrators to retrieve specific datasets, often filtered by time range or data type, to investigate system behavior, bottlenecks, or anomalies within the Spectrum Scale cluster. The output is typically in a specialized format designed for further processing by IBM's internal analysis tools, rather than direct human readability. It is an essential tool for deep-dive investigations into Spectrum Scale cluster health and performance.


title: CAVEATS
content:
This command is specific to <b>IBM Spectrum Scale</b> (GPFS) environments and is not a standard Linux utility found on generic distributions. It critically requires that analysis data has already been actively collected and stored by the `sc_analysis` command or daemon. The output format is highly specialized, typically machine-readable for IBM's diagnostic tools, and generally <i>not</i> intended for direct human consumption or parsing with standard text utilities. Running this command on large datasets or for extended time ranges can generate extremely large output files, potentially consuming significant disk space.


title: OUTPUT DATA FORMAT
content:
The data generated by `sc_analysis_dump` is often in a highly optimized, internal binary or structured format (e.g., Protobuf or similar) specifically designed for consumption by IBM's proprietary analysis tools and scripts. It is generally <i>not</i> intended for direct human interpretation or parsing with standard text processing tools like `grep` or `awk`.


title: PREREQUISITES FOR USAGE
content:
For `sc_analysis_dump` to function correctly, the system must be an <b>IBM Spectrum Scale</b> cluster node, and crucially, analysis data must have been actively collected and stored by the `sc_analysis` daemon or process prior to running this command. Without pre-collected data, the command will have nothing to dump.


title: HISTORY
content:
The `sc_analysis_dump` command has been an integral part of the diagnostic toolkit for <b>IBM General Parallel File System (GPFS)</b>, which was later rebranded as <b>IBM Spectrum Scale</b>. It was developed by IBM to support its high-performance, distributed file system, enabling administrators and support staff to deeply analyze system behavior. It has evolved alongside the file system, adapting to new data types and performance metrics introduced in successive Spectrum Scale versions, ensuring comprehensive analysis capabilities for complex enterprise storage environments.


title: PARAMETERS
content:
<b><i>&lt;trace_file1&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;The path to the first system call trace file to be compared.<br><br><b><i>&lt;trace_file2&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;The path to the second system call trace file to be compared.<br><br>


title: DESCRIPTION
content:
The <i>sc_tracediff</i> command is a specialized utility designed to compare two system call trace files, typically generated by the <i>sc_trace</i> tool. It highlights the differences between the system call sequences, arguments, and return values recorded in the two input files. This command is particularly useful in embedded Linux development and debugging scenarios for purposes such as regression testing, analyzing performance changes, or identifying behavioral shifts between two runs of an application or system. By providing a detailed comparison of system call interactions, <i>sc_tracediff</i> helps developers quickly pinpoint discrepancies that might indicate bugs, unexpected behavior, or changes in execution flow.


title: CAVEATS
content:
<i>sc_tracediff</i> is not a standard, universally available Linux command. It is typically part of specific SDKs and toolchains, such as those provided by Renesas for embedded Linux development. <br>Its functionality is dependent on the format of trace files generated by the <i>sc_trace</i> utility. <br>Command-line options for <i>sc_tracediff</i> are not widely documented and may be limited or specific to particular versions of the <i>sc_trace</i> utility suite.


title: USAGE CONTEXT
content:
Primarily utilized in development workflows involving embedded Linux systems, <i>sc_tracediff</i> assists in ensuring software consistency. Developers capture traces before and after code changes or system updates, then use this command to verify that system call interactions remain as expected or to identify the root cause of observed regressions.


title: INPUT FILE FORMAT
content:
The input files (<i>&lt;trace_file1&gt;</i> and <i>&lt;trace_file2&gt;</i>) are expected to be in the specific format produced by the <i>sc_trace</i> utility. This format typically includes detailed information about each system call, such as its sequence number, timestamp, process ID, thread ID, system call name, arguments, and return value.


title: HISTORY
content:
<i>sc_tracediff</i> emerged as part of the <i>sc_trace</i> utility suite, developed primarily for deep debugging and analysis in embedded Linux environments. Its development focuses on providing detailed insights into system call interactions on target hardware, facilitating comparison and regression analysis for software development and validation on platforms where traditional debugging tools might be limited.


title: PARAMETERS
content:
<b><I>action</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the operation to perform. Hypothetical actions include <b>list</b> (to show TTL-managed items), <b>expire</b> (to force immediate expiration), <b>monitor</b> (to observe TTL activity), or <b>status</b> (to display system health related to TTLs).<br><br><b>-t <type></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Filters or specifies the <I>type</I> of TTL-managed entity to target (e.g., 'cache', 'session', 'token').<br><br><b>-i <id></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies a particular entity by its unique <I>ID</I> when performing an action like <b>expire</b>.<br><br><b>-f</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Forces an immediate expiration action, potentially bypassing confirmation prompts or soft deletion mechanisms.<br><br><b>-v</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Enables verbose output, providing more detailed information about the command's execution and the state of TTL-managed entities.<br><br>


title: DESCRIPTION
content:
The command <b>sc_ttlexp</b> is not a standard, widely documented Linux command found in general-purpose distributions. Its name, however, strongly suggests a utility designed for managing or triggering the expiration of entities based on a Time-To-Live (TTL) mechanism. Such entities could hypothetically include cached data, session tokens, network entries, or security contexts that have a defined lifespan.<br><br>In a speculative context, this command would likely be part of a larger system (e.g., a caching service, a session management daemon, or a security framework) to ensure that stale or expired data is properly invalidated and removed, maintaining system integrity and resource efficiency. It would facilitate manual intervention for expiration events or provide insight into TTL-managed resources within its specific system.


title: CAVEATS
content:
The command <b>sc_ttlexp</b> is not a standard, widely documented utility in mainstream Linux distributions (e.g., Debian, Ubuntu, Fedora, CentOS). Its existence and functionality are highly speculative, inferred solely from its name (<I>sc_</I> likely indicating 'Service Control' or 'System Cache', and <I>ttlexp</I> for 'Time-To-Live expiration').<br><br>If encountered, it is likely part of a very specific, proprietary application, an internal tool, or a component of a niche system (e.g., SmartCard utilities, specific caching solutions). Users should not expect this command to be available by default or have standard man page documentation.


title: CONTEXT OF USE (HYPOTHETICAL)
content:
While hypothetical, a command like <b>sc_ttlexp</b> would typically be used by system administrators or developers working with systems that heavily rely on Time-To-Live (TTL) for resource management, security token validation, or data consistency. It would provide a programmatic interface to interact with the underlying TTL expiration logic, allowing for manual intervention or inspection of expiration states.


title: IMPLEMENTATION CONSIDERATIONS (HYPOTHETICAL)
content:
If such a command were to be implemented, it would require access to the internal state of the system managing TTLs. This could involve direct interaction with kernel modules, specific daemon processes, or a dedicated API, depending on the system's architecture. Robust error handling, logging, and permission management would be crucial for its secure and reliable operation.


title: HISTORY
content:
As <b>sc_ttlexp</b> is not a standard Linux command, there is no public development history or widespread usage documentation. Its origin, if it exists, would be specific to the particular system or application it serves, likely developed to manage internal Time-To-Live mechanisms unique to that environment. It would not be part of the GNU core utilities or standard system management tools.


title: PARAMETERS
content:
<b><b>-w</b> <i>&lt;pcap_file&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Writes the converted PCAP data to the specified output file. If omitted, output is directed to standard output (<i>stdout</i>).<br><br><b><b>-D</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Enables verbose debug output during the conversion process.<br><br><b><b>-h</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays a help message with command usage and exits.<br><br><b><b>-v</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays the version information of <i>sc_warts2pcap</i> and exits.<br><br><b><b>-N</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Suppresses the writing of <i>scamper</i>'s measurement metadata into the <i>pcap</i> file.<br><br><b><b>-S</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Forces the writing of <i>scamper</i>'s measurement metadata into the <i>pcap</i> file. This is often the default behavior.<br><br><b><b>-C</b> <i>&lt;snaplen&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets the <i>pcap</i> snapshot length (capture length) in bytes, limiting the amount of data captured per packet.<br><br><b><b>-i</b> <i>&lt;interface&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets the <i>pcap</i> interface name in the <i>pcap</i> global header.<br><br><b><b>-L</b> <i>&lt;linktype&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the <i>pcap</i> link-layer type (e.g., <i>EN10MB</i> for Ethernet) for the output file.<br><br><b><b>-t</b> <i>&lt;offset&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Applies a time offset in seconds to the packet timestamps in the generated <i>pcap</i> file.<br><br><b><b>-T</b> <i>&lt;type&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the type of <i>scamper</i> trace measurements to convert (e.g., <i>icmp-echo</i>, <i>udp-traceroute</i>, <i>tcp-connect</i>).<br><br><b><b>-B</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Writes the <i>pcap</i> file in big-endian byte order.<br><br><b><b>-s</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Writes the <i>pcap</i> file in small-endian byte order (default on most systems).<br><br>


title: DESCRIPTION
content:
<i>sc_warts2pcap</i> is a specialized utility from the <i>scamper</i> suite, designed to convert network measurement data stored in <i>warts</i> format into the widely recognized <i>pcap</i> (Packet CAPture) format. <i>Warts</i> files are generated by <i>scamper</i>, a tool used for active Internet topology discovery and measurement, containing detailed records of probes and replies (e.g., from traceroutes or pings).<br><br>The primary purpose of <i>sc_warts2pcap</i> is to enable the analysis of <i>scamper</i>'s raw measurement data using standard network protocol analyzers like Wireshark, <i>tcpdump</i>, or <i>tshark</i>. By transforming the data into <i>pcap</i>, users can visualize packet-level interactions, inspect headers, and apply various filtering techniques, providing a deeper understanding of the network events captured by <i>scamper</i>. This conversion utility is essential for researchers and network engineers who require detailed packet-level visibility into their <i>scamper</i>-derived datasets.


title: CAVEATS
content:
<ul><li><b>Data Fidelity:</b> Not all intricate details from <i>warts</i> files directly map to standard <i>pcap</i> packets. Some <i>scamper</i>-specific metadata might be lost or encoded in ways that require specific interpretation in <i>pcap</i>.</li><li><b>Source Interpretation:</b> To properly analyze the converted <i>pcap</i>, users should be familiar with <i>scamper</i>'s measurement methodologies, including the specific ICMP types, UDP/TCP ports, and packet structures used for probes.</li><li><b>File Integrity:</b> The command assumes valid and well-formed <i>warts</i> input files. Corrupted or malformed <i>warts</i> data can lead to conversion errors or incomplete output.</li></ul>


title: INPUT AND OUTPUT FLEXIBILITY
content:
<i>sc_warts2pcap</i> offers flexible input and output options. It can read <i>warts</i> data from one or more specified files, or from standard input (<i>stdin</i>) by passing '<b>-</b>' as a filename. The converted <i>pcap</i> output is written to standard output (<i>stdout</i>) by default, but can be redirected to a specific file using the '<b>-w</b>' option. This design facilitates seamless integration into shell pipelines for automated processing.


title: IMPORTANCE OF TRACE TYPES
content:
The '<b>-T</b>' option is vital for accurate conversions. <i>Scamper</i> can perform various types of network measurements (e.g., ICMP echo requests, UDP-based traceroutes, TCP-based connect probes). Specifying the correct trace type with '<b>-T</b>' ensures that <i>sc_warts2pcap</i> accurately parses the corresponding <i>warts</i> records and generates a <i>pcap</i> representation that correctly reflects the original probes and their replies, crucial for meaningful analysis.


title: HISTORY
content:
<i>sc_warts2pcap</i> is an integral component of the <i>scamper</i> measurement suite, which originated from research efforts at the Cooperative Association for Internet Data Analysis (CAIDA). Developed to improve Internet topology mapping, <i>scamper</i> generates detailed network measurement data in its proprietary <i>warts</i> format. <i>sc_warts2pcap</i> was created as a crucial bridge, enabling the conversion of this specialized data into the universally recognized <i>pcap</i> format. This interoperability ensures that <i>scamper</i>'s rich datasets can be readily analyzed using standard network analysis tools, thus broadening their accessibility and utility for network researchers and engineers.


title: PARAMETERS
content:
<b>-p</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Pretty print the output in JSON format with human-readable indentation.<br><br><b>-r</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Produce raw (un-indented) JSON output, often preferred for scripting and large data processing.<br><br><b>-m</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Include metadata fields in the output, providing additional information about the measurement context.<br><br><b>-o <file></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Write the converted output to the specified <I>file</I> instead of standard output (stdout).<br><br><b>-J</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Force output in JSON format. This is often the default behavior in newer versions but can be explicitly specified for clarity.<br><br><b>-t</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Force output in plain text format, typically tab-separated values. This was the default in older versions of the utility.<br><br><b>-S <offset></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Skip records in the input file until the specified byte <I>offset</I> is reached. Useful for resuming processing or partial reads of large files.<br><br><b>-P <length></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Process only a specified <I>length</I> of bytes from the input file, starting from the current position or after any -S offset.<br><br><b>-d <directory></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specify a <I>directory</I> containing custom schema files for interpreting extended or non-standard <I>warts</I> structures. Rarely used by typical users.<br><br><b>-F</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Print the version information of the utility and exit.<br><br><b>-h</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Print a help message with usage instructions and available options, then exit.<br><br>


title: DESCRIPTION
content:
The <b>sc_warts2text</b> command is a crucial utility within the <I>scamper</I> suite, specifically designed to convert binary <I>warts</I> files into a human-readable text format. <I>Warts</I> files serve as the native, efficient binary output format for network measurement data collected by <I>scamper</I> during active probing campaigns, containing detailed results from operations like traceroutes, pings, and various other internet path measurements. <br><br>This command empowers network researchers, operators, and analysts to easily access and inspect the granular measurement data. It facilitates the conversion into widely compatible formats such as JSON or plain text (often tab-separated), making the complex binary data accessible for further processing, scripting, statistical analysis, and seamless integration with other data processing tools and platforms. <b>sc_warts2text</b> provides a set of flexible options to precisely control the output format, verbosity, and file handling, catering to diverse analysis needs.


title: CAVEATS
content:
When processing very large <I>warts</I> files, the resulting text output can be extremely verbose and may consume significant disk space or terminal buffer. Users should consider piping output to other tools (e.g., <I>less</I>, <I>grep</I>, <I>jq</I>) or redirecting to a file for efficient handling. The default output format (<I>JSON</I> vs. plain <I>text</I>) might vary slightly depending on the <I>scamper</I> version; explicit use of <I>-J</I> or <I>-t</I> is recommended for consistent results across different environments.


title: WARTS FILE FORMAT
content:
The <I>warts</I> file format is a proprietary binary format designed by CAIDA to store network measurement results efficiently. It supports various types of measurements (e.g., traceroute, ping, active probing) and is optimized for the compact storage and high-speed retrieval of large datasets generated by <I>scamper</I>. <b>sc_warts2text</b> is the primary command-line tool for converting this specialized binary format into a more widely accessible text representation.


title: INTEGRATION WITH JQ
content:
When utilizing the JSON output mode (either by default or explicitly with the <I>-J</I> option), the output of <b>sc_warts2text</b> can be seamlessly piped into the <I>jq</I> command-line JSON processor. This powerful combination allows for advanced filtering, parsing, and manipulation of the measurement data. For example, to extract all source IP addresses from a <I>warts</I> file containing traceroute records, one could use: <I>sc_warts2text file.warts -J | jq '.records[].srcip'</I>.


title: HISTORY
content:
<b>sc_warts2text</b> is an integral component of the <I>scamper</I> measurement tool suite, primarily developed and maintained by the CAIDA (Cooperative Association for Internet Data Analysis) project. <I>Scamper</I> was initially created to perform highly scalable and flexible active network measurements, producing its results in the efficient binary <I>warts</I> format. As such, <b>sc_warts2text</b> emerged as a crucial companion tool, empowering researchers and network operators to extract and interpret this complex binary data without requiring specialized programming. Its development has closely mirrored that of <I>scamper</I>, evolving to support new <I>warts</I> file versions and adapting to modern data interchange standards like JSON, reflecting the increasing demand for structured data suitable for automated analysis and visualization.


title: SYNOPSIS
content:
sc_wartscat [ -N | -n | -v | -w ] [ -d <I>debug_level</I> ] [ -o <I>output_file</I> ] [ <I>file</I> ... ]


title: PARAMETERS
content:
<b>-N</b><br>&nbsp;&nbsp;&nbsp;&nbsp;<I>Suppress new file messages.</I> Prevents sc_wartscat from printing 'start of new file' messages to standard error when concatenating multiple input files.<br><br><b>-n</b><br>&nbsp;&nbsp;&nbsp;&nbsp;<I>Enable new file messages.</I> Forces sc_wartscat to print 'start of new file' messages to standard error. This is the default behavior.<br><br><b>-v</b><br>&nbsp;&nbsp;&nbsp;&nbsp;<I>Print Warts version.</I> Displays the version number of the Warts library used by the utility, then exits.<br><br><b>-w</b><br>&nbsp;&nbsp;&nbsp;&nbsp;<I>Print Warts format description.</I> Displays a concise description of the Warts binary format, then exits.<br><br><b>-d <I>debug_level</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;<I>Set debugging level.</I> Controls the verbosity of debugging output. <I>debug_level</I> can range from 0 (no debug) to 3 (maximum debug).<br><br><b>-o <I>output_file</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;<I>Specify output file.</I> Directs the concatenated Warts data to the specified <I>output_file</I> instead of standard output.<br><br><b><I>file</I> ...</b><br>&nbsp;&nbsp;&nbsp;&nbsp;<I>Input Warts files.</I> One or more paths to Warts files to be concatenated. If no files are specified, sc_wartscat reads from standard input.<br><br>


title: DESCRIPTION
content:
sc_wartscat is a utility from the <I>wats-tool</I> suite, designed to concatenate multiple Warts files into a single output stream or file. Warts files are a binary format used by the <I>scamper</I> tool to store network measurement data, primarily from traceroute-like probes. These files often contain a series of 'cycles' or measurement runs.<br><br>The primary purpose of sc_wartscat is to combine data from various <I>scamper</I> measurement outputs, making it easier to process or analyze a larger dataset as a single unit. For instance, if <I>scamper</I> was run multiple times, or measurements were distributed across different machines, sc_wartscat can merge these individual Warts files. It operates similarly to the standard <I>cat</I> command but is specifically tailored for the Warts binary format, ensuring proper handling of the file structure. Output can be directed to standard output or a specified file.


title: CAVEATS
content:
sc_wartscat is specifically designed for the Warts binary format; using it on non-Warts files will result in errors or corrupted output. The <I>wats-tool</I> suite, including sc_wartscat, is primarily used in network measurement research and may not be widely available in standard Linux distributions by default.


title: WARTS FILE FORMAT
content:
The Warts file format is a compact, binary format specifically designed to store network topology measurement data, particularly from <I>scamper</I> probes. It efficiently encodes various record types, such as traceroute paths, ping measurements, and link information. Its binary nature makes it efficient for storage and retrieval, though it requires specialized tools like <I>sc_wartscat</I> or <I>sc_warts2text</I> for manipulation and interpretation.


title: HISTORY
content:
sc_wartscat is part of the <I>wats-tool</I> suite, developed by the <I>Center for Applied Internet Data Analysis</I> (CAIDA). CAIDA is a leading research center focused on Internet infrastructure and dynamics. The <I>wats-tool</I> suite emerged from the need to efficiently store, process, and analyze large volumes of network measurement data collected using tools like <I>scamper</I>. sc_wartscat plays a fundamental role in the data pipeline, enabling researchers to aggregate raw measurement files before further analysis. Its development reflects CAIDA's commitment to providing open-source tools for network research.


title: SYNOPSIS
content:
<b>sc_wartsdump</b> [<i>options</i>] <i>&lt;warts_file&gt;</i><br><b>sc_wartsdump</b> [<i>options</i>] <b>-</b>


title: PARAMETERS
content:
<b><b>-v</b>, <b>--verbose</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Increases verbosity, showing more detailed processing information.<br><br><b><b>-x</b>, <b>--xml</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Outputs the Warts file content in XML format.<br><br><b><b>-j</b>, <b>--json</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Outputs the Warts file content in JSON format.<br><br><b><b>-d</b>, <b>--dump-records</b> <i>&lt;record_types&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Dumps only specific record types. <i>&lt;record_types&gt;</i> is a comma-separated list (e.g., 'tr' for traceroute, 'hp' for hop, 'lp' for loop).<br><br><b><b>-s</b>, <b>--statistics</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Prints summary statistics about the Warts file records instead of dumping full content.<br><br><b><b>-l</b>, <b>--list-records</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Lists all record types found in the Warts file.<br><br><b><b>-o</b>, <b>--output</b> <i>&lt;file&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Writes output to the specified file instead of standard output.<br><br><b><b>-p</b>, <b>--pretty-print</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Pretty-prints XML/JSON output for readability.<br><br><b><b>-h</b>, <b>--help</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays a help message and exits.<br><br>


title: DESCRIPTION
content:
<i>sc_wartsdump</i> is a specialized utility from the <I>scamper</I> suite, designed to parse and display the contents of Warts files. Warts is a binary file format primarily used to store network measurement data collected by the <I>scamper</I> tool, such as traceroute, ping, and other active probing results. This command allows users to extract and view this complex binary data in various human-readable formats, including plain text, XML, and JSON. It is invaluable for researchers and network engineers analyzing large datasets of Internet topology and performance measurements. The tool can output specific record types, provide summary statistics, or dump the entire file content, making it flexible for different analytical needs.


title: CAVEATS
content:
<i>sc_wartsdump</i> is not a standard Linux utility and requires the <I>scamper</I> software suite to be installed on the system. It is primarily used by researchers and network engineers working with Internet topology data, not for general-purpose system administration. The Warts file format itself can be complex, and understanding its structure is beneficial for effective use of this command.


title: PIPING INPUT
content:
<i>sc_wartsdump</i> can read Warts data from standard input, making it useful in pipelines. For example, `<b>cat file.warts | sc_wartsdump -x -</b>` would dump the XML content of `<i>file.warts</i>`. This allows for flexible integration with other command-line tools.


title: UNDERSTANDING WARTS RECORDS
content:
The Warts format encapsulates various types of measurement records, such as traceroute results, ping data, and hop-by-hop details. Users should consult the Warts format specification (<i>warts(5)</i>) to fully understand the meaning of the data output by <i>sc_wartsdump</i>.


title: HISTORY
content:
<i>sc_wartsdump</i> is an integral part of the <I>scamper</I> project, developed by the Center for Applied Internet Data Analysis (CAIDA). CAIDA is a research organization dedicated to improving the Internet through data-driven analysis. The <I>scamper</I> suite, including <I>sc_wartsdump</I>, was created to facilitate large-scale, high-fidelity active measurement of Internet topology and performance. Its development reflects the ongoing need for robust tools to collect, process, and analyze complex network measurement data, evolving alongside the Internet's growth and increasing complexity.


title: PARAMETERS
content:
<b>-A <ip/prefix></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Filter by source or destination <I>IP address</I> or <I>prefix</I>.<br><br><b>-D <ip/prefix></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Filter by destination <I>IP address</I> or <I>prefix</I>.<br><br><b>-S <ip/prefix></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Filter by source <I>IP address</I> or <I>prefix</I>.<br><br><b>-a <asn></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Filter by source or destination <I>ASN</I>.<br><br><b>-d <asn></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Filter by destination <I>ASN</I>.<br><br><b>-s <asn></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Filter by source <I>ASN</I>.<br><br><b>-F <flow_id></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Filter by specific <I>flow ID</I>.<br><br><b>-t <start>:<end></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Filter by <I>timestamp range</I> (UNIX epoch seconds or YYYYMMDDHHMMSS format). Start or end can be omitted.<br><br><b>-T <type></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Filter by record <I>type</I> (e.g., <I>ping</I>, <I>tr</I>, <I>cycle</I>, <I>dns</I>).<br><br><b>-M <max_rtt></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Filter out records with RTT greater than <I>max_rtt</I> (milliseconds).<br><br><b>-m <min_rtt></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Filter out records with RTT less than <I>min_rtt</I> (milliseconds).<br><br><b>-H <max_hops></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Filter out traceroutes with more than <I>max_hops</I>.<br><br><b>-h <min_hops></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Filter out traceroutes with less than <I>min_hops</I>.<br><br><b>-e</b><br>&nbsp;&nbsp;&nbsp;&nbsp;<B>Exclude</B> records that match the specified criteria (invert filter logic).<br><br><b>-i <file></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Read input from <I>file</I> instead of standard input.<br><br><b>-o <file></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Write output to <I>file</I> instead of standard output.<br><br><b>-v</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Enable verbose output, showing progress and matched records.<br><br><b>-P</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Print record header to stdout.<br><br><b>-X</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Print flow records in hexadecimal format.<br><br><b>-x</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Pretty-print warts records to stdout (useful for debugging and human readability).<br><br><b>-w</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Write matching warts records to stdout (this is the default behavior if not using <B>-o</B>, <B>-X</B>, <B>-x</B>, or <B>-P</B>).<br><br>


title: DESCRIPTION
content:
sc_wartsfilter is a command-line utility from the CAIDA Scamper suite designed to filter binary Warts files. Warts files store network measurement data, such as traceroutes and pings. This tool allows users to extract specific subsets of data based on various criteria, including source/destination IP addresses or prefixes, Autonomous Systems (ASNs), flow IDs, timestamp ranges, and record types (e.g., traceroute or ping records). It also supports filtering by round-trip times (RTT) and hop counts. It's essential for processing large datasets and isolating relevant measurements for analysis, reading from standard input or a specified file and writing filtered Warts data to standard output or a designated file.


title: CAVEATS
content:
Warts files are a custom binary format, making direct inspection difficult without specific tools like <B>sc_wartsfilter</B> or <B>sc_wartsdump</B>. ASN filtering relies on available IP-to-ASN mappings, which may not be perfectly up-to-date or comprehensive within the context of the Warts file's collection time.


title: INPUT/OUTPUT FORMAT
content:
sc_wartsfilter primarily operates on <I>Warts</I> files, a custom binary format developed by CAIDA for storing network measurement data efficiently. The filtered output, by default, is also in the Warts format, preserving the structure of the records. When options like <B>-X</B> or <B>-x</B> are used, the output becomes human-readable representations for debugging or specific analysis.


title: FILTERING LOGIC
content:
Multiple filtering options specified on the command line are typically combined with a logical <B>AND</B> operation. For instance, using <B>-S</B> and <B>-D</B> simultaneously will only match records that satisfy <I>both</I> the source and destination criteria. The <B>-e</B> option inverts the final result of this combined logic, effectively <B>excluding</B> records that match all other specified criteria.


title: HISTORY
content:
sc_wartsfilter is a core component of the <B>Scamper</B> measurement tool suite, developed by <B>CAIDA</B> (Center for Applied Internet Data Analysis). It was created to facilitate the large-scale analysis of active network topology measurements by providing a robust way to process and filter the binary Warts datasets generated by Scamper. Its development is ongoing as part of CAIDA's continuous effort to provide tools for Internet research and network analysis.


title: PARAMETERS
content:
<b><b>input_file.warts</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;The path to the input <i>.warts</i> file that needs to be fixed. This argument is mandatory and must specify an existing file.<br><br><b><b>output_file.warts</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;The path where the fixed <i>.warts</i> file will be written. This argument is mandatory and will create or overwrite the specified file.<br><br>


title: DESCRIPTION
content:
<b>sc_wartsfix</b> is a utility program primarily used in conjunction with CAIDA's <b>scamper</b> network measurement tool. Its main purpose is to rectify common issues and inconsistencies found within <i>.warts</i> files, which are binary data files used by <b>scamper</b> to store raw network measurement results (e.g., traceroutes, pings). These issues can include malformed headers, corrupt data segments, or other integrity problems that prevent proper parsing or analysis of the measurement data. By "fixing" these files, <b>sc_wartsfix</b> helps ensure the reliability and usability of collected network measurement data, making it suitable for subsequent processing with other <b>scamper</b> utilities or analysis tools. It is not a standard Linux command but rather a specialized tool distributed as part of the <b>scamper</b> software package.


title: CAVEATS
content:
<b>sc_wartsfix</b> is not a standard Linux command; it is distributed as part of CAIDA's <b>scamper</b> suite. It strictly requires two file paths (input and output) as arguments and does not support standard input/output (stdin/stdout). It is specifically designed for the <i>.warts</i> file format and may not be able to fix all types of file corruption, only known structural or header issues.


title: TYPICAL USE CASE
content:
<b>sc_wartsfix</b> is typically used as a post-processing step for <b>scamper</b> measurement data. If a <i>.warts</i> file generated by <b>scamper</b> is found to be unreadable or malformed by other <i>.warts</i> utilities (like <b>sc_warts2json</b> or <b>sc_warts2text</b>), <b>sc_wartsfix</b> is employed to attempt to repair the file before further analysis. This ensures that valuable measurement data is not lost due to minor corruption.


title: HISTORY
content:
<b>sc_wartsfix</b> emerged as part of the <b>scamper</b> software distribution, developed by the Center for Applied Internet Data Analysis (CAIDA). Its necessity arose from the challenges of collecting vast amounts of network measurement data, which can occasionally result in <i>.warts</i> files with structural inconsistencies or minor corruptions due to network conditions, system issues, or unexpected program termination. As <b>scamper</b> became a widely used tool for large-scale active probing, <b>sc_wartsfix</b> was developed to provide a straightforward method for ensuring the integrity and usability of these critical measurement datasets, facilitating their subsequent analysis and archival.


title: SYNOPSIS
content:
<b>scala</b> [<i>options</i>] [<i>scriptfile</i> | <i>classname</i>] [<i>args...</i>]<br><b>scala</b> [<i>options</i>] (to start REPL)


title: PARAMETERS
content:
<b><b>-classpath</b> <i>&lt;path&gt;</i> | <b>-cp</b> <i>&lt;path&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the user class path for loading classes and resources. This is crucial for including external libraries or your own compiled code.<br><br><b><b>-D</b><i>&lt;property&gt;</i>=<i>&lt;value&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets a Java system property. Useful for configuring applications that rely on system properties (e.g., <i>-Dmy.setting=value</i>).<br><br><b><b>-J</b><i>&lt;flag&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Passes a raw flag directly to the underlying Java runtime. This is used for JVM tuning, such as setting memory limits (e.g., <i>-J-Xmx1G</i>).<br><br><b><b>-X</b><i>&lt;option&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Passes an option to the Scala runtime, often for experimental or advanced features/diagnostics.<br><br><b><b>-i</b> <i>&lt;file&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Reads and executes commands from the specified file, then enters the REPL. Useful for loading common definitions or setup code into the interactive session.<br><br><b><b>-e</b> <i>&lt;command&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Executes the given command string as a Scala script and then enters the REPL. Useful for one-liners before interacting.<br><br><b><b>-howtorun:script</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Treats arguments as a Scala script file to be executed. This is the default behavior when a file argument is provided.<br><br><b><b>-howtorun:object</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Treats the first argument as the name of a top-level Scala object (containing a <i>main</i> method) to run.<br><br><b><b>-howtorun:jar</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Treats the first argument as a JAR file to be executed, typically one with a <i>Main-Class</i> entry in its manifest.<br><br><b><b>-howtorun:repl</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Forces <b>scala</b> to enter the interactive REPL. This is the default when no arguments are given.<br><br><b><b>-version</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Prints the Scala product version and exits.<br><br><b><b>-help</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays a comprehensive list of available options and their descriptions.<br><br>


title: DESCRIPTION
content:
The <b>scala</b> command is the primary command-line interface for executing Scala programs and scripts, as well as initiating the interactive Scala Read-Eval-Print Loop (REPL). <br><br>Scala is a powerful multi-paradigm programming language designed to express common programming patterns in a concise, elegant, and type-safe way. It runs on the Java Virtual Machine (JVM) and is interoperable with Java code. <br><br>When invoked without arguments, <b>scala</b> launches the REPL, providing an immediate environment for experimenting with Scala code, testing snippets, and learning the language interactively. When provided with a script file (e.g., with a <i>.scala</i> extension) or the name of a compiled Scala object (class file), it executes the specified program. It acts as an interpreter for Scala source files or as a launcher for compiled bytecode, relying on the underlying Java runtime environment.


title: CAVEATS
content:
<b>scala</b> requires a Java Development Kit (JDK) or Java Runtime Environment (JRE) to be installed and accessible in the system's PATH, as it relies heavily on the JVM.<br><br>Running Scala scripts directly with <b>scala</b> can incur a noticeable startup overhead due to JVM initialization, especially for small scripts. For compiled applications, this overhead is typically paid once at launch.<br><br>Memory usage can be significant, particularly for complex applications or prolonged REPL sessions, as the JVM and Scala runtime consume considerable resources.


title: THE REPL (READ-EVAL-PRINT LOOP)
content:
The Scala REPL is an invaluable tool for learning and prototyping. It allows users to type Scala expressions or statements directly into the console, which are then immediately evaluated, and the result is printed. This interactive feedback loop significantly speeds up development and experimentation compared to traditional compile-run cycles.


title: EXECUTION MODES
content:
The <b>scala</b> command can execute code in several ways: <br>1. <i>Interpreting a script file:</i> <pre>scala MyScript.scala</pre><br>2. <i>Running a compiled class:</i> <pre>scala MyPackage.MyObject</pre> (requires <i>MyObject.class</i> to be on the classpath)<br>3. <i>Launching a JAR file:</i> <pre>scala -howtorun:jar myapp.jar</pre><br>4. <i>Interactive REPL:</i> <pre>scala</pre> (without arguments)<br>Understanding these modes is key to effectively using the <b>scala</b> command for different development and deployment scenarios.


title: HISTORY
content:
The Scala language and its associated tools, including the <b>scala</b> command, were created by Martin Odersky at EPFL (École Polytechnique Fédérale de Lausanne) in Switzerland. The first public release of Scala was in 2004. The <b>scala</b> command has been a fundamental component of the Scala distribution since its inception, providing immediate access to the interpreter and the ability to execute Scala programs directly from the command line. Its design reflects Scala's core philosophy of blending object-oriented and functional programming paradigms on the robust Java Virtual Machine.


title: SYNOPSIS
content:
<i>scala-cli</i> <I>[options]</I> <I>[subcommand]</I> <I>[subcommand-options]</I> <I>[arguments...]</I><br><br>Common usage examples:<br><br><i>scala-cli</i> <I>run</I> <I>MyScript.scala</I> <I>[--] [script-arguments...]</I><br><i>scala-cli</i> <I>compile</I> <I>.</I><br><i>scala-cli</i> <I>test</I> <I>.</I><br><i>scala-cli</i> <I>repl</I><br><i>scala-cli</i> <I>package</I> <I>.</I> <I>-o</I> <I>my-app</I>


title: PARAMETERS
content:
<b><I>run</I> <I>[sources...]</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Executes Scala source files or a compiled application. Often used for scripting and direct execution.<br><br><b><I>compile</I> <I>[sources...]</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Compiles Scala source files into JVM bytecode.<br><br><b><I>test</I> <I>[sources...]</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Discovers and runs tests defined in your project or source files.<br><br><b><I>repl</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Starts an interactive Scala REPL (Read-Eval-Print Loop) with configured dependencies.<br><br><b><I>package</I> <I>[sources...]</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Packages the application into various formats, such as JAR, native executable (via GraalVM), or other distributions.<br><br><b><I>setup</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Helps install or configure necessary components like Bloop, Coursier, or the CLI itself.<br><br><b><I>clean</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Removes temporary build files and caches generated by <i>scala-cli</i>.<br><br><b><I>config</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Manages configuration options for <i>scala-cli</i>.<br><br><b><I>export</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Exports a <i>scala-cli</i> project to a build tool definition (e.g., sbt, Mill, Scala.js).<br><br><b><B>--version</B></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays the installed version of <i>scala-cli</i>.<br><br><b><B>--power</B></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Enables experimental and potentially unstable 'power' features, offering advanced control.<br><br><b><B>--help</B>, <B>-h</B></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Shows help information for the main command or a specific subcommand.<br><br>


title: DESCRIPTION
content:
<i>scala-cli</i> is a modern, feature-rich command-line interface for Scala development, designed to simplify common tasks like running scripts, compiling code, managing dependencies, and packaging applications. It aims to provide a fast and user-friendly experience, making it easier to get started with Scala, particularly for scripting and small to medium-sized projects.<br><br>It acts as a powerful orchestrator, capable of running single Scala files, entire directories, or even mixed Scala/Java sources. It intelligently resolves dependencies, integrates with <i>bloop</i> for fast incremental compilation, and offers features like testing, packaging native executables (via GraalVM), and creating project definitions. It can be seen as a successor to the traditional <i>scala</i> runner, providing a more robust and complete development environment out of the box, suitable for both beginners and experienced Scala developers.


title: CAVEATS
content:
Dependency resolution can sometimes incur a noticeable delay on the first run due to downloading artifacts. While <i>scala-cli</i> simplifies many aspects, large, complex multi-module projects might still find more established build tools like sbt or Mill more suitable for highly customized or intricate build logic. Features enabled via <B>--power</B> are experimental and subject to change or removal in future versions.


title: SHEBANG SUPPORT
content:
<i>scala-cli</i> files can be made executable scripts using a shebang line like <B>#!/usr/bin/env scala-cli</B>. This allows them to be run directly from the shell like any other script without explicit invocation via '<i>scala-cli run</i>'.


title: DIRECTIVES
content:
Source files can include special <B>//> using</B> directives to specify dependencies, Scala versions, JVM options, and other project configurations directly within the source code. This eliminates the need for separate build files for simple projects, simplifying setup and making scripts self-contained.


title: BUILD TOOL INTEGRATION
content:
<i>scala-cli</i> integrates with and can generate project files for other established Scala build tools like sbt, Mill, and more. This offers flexibility for projects that might start as simple scripts but eventually require the robust features of a full-fledged build system.


title: HISTORY
content:
<i>scala-cli</i> emerged as a successor and modern alternative to the aging <i>scala</i> command-line runner. It was developed by VirtusLab and later became a part of the Scala organization's official tooling, aiming to provide a more integrated, faster, and user-friendly experience for Scala developers. Its development was driven by the desire to improve the 'getting started' experience with Scala, streamline common development workflows, and leverage modern build infrastructure like Bloop for fast incremental compilation, addressing long-standing pain points in the Scala ecosystem. It quickly became the recommended command-line tool for scripting and lightweight project management in Scala.


title: PARAMETERS
content:
<b>-u <i>USER</i>, --user=<i>USER</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Map the current user to <i>USER</i> inside the cage. The user ID is remapped within the user namespace.<br><br><b>-g <i>GROUP</i>, --group=<i>GROUP</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Map the current user's primary group to <i>GROUP</i> inside the cage. The group ID is remapped within the user namespace.<br><br><b>-b <i>DIR</i>, --bind=<i>DIR</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Bind mount an existing directory <i>DIR</i> from the host into the cage at the same path. Can be specified multiple times.<br><br><b>-m <i>TYPE:DEVICE:DIR:OPTIONS</i>, --mount=<i>TYPE:DEVICE:DIR:OPTIONS</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Mount a filesystem or device into the cage. For example, <i>tmpfs:none:/tmp:size=10m</i>.<br><br><b>-t <i>SIZE</i>, --tmpfs=<i>SIZE</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Mount a <i>tmpfs</i> at <i>/tmp</i> inside the cage, with an optional <i>SIZE</i> limit (e.g., <i>10M</i>).<br><br><b>-e <i>VAR=VALUE</i>, --env=<i>VAR=VALUE</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Set an environment variable inside the cage for the executed command.<br><br><b>--proc</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Mount a private <i>/proc</i> filesystem instance inside the cage, isolating process information.<br><br><b>--devfs</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Mount a private <i>/dev</i> filesystem instance inside the cage, limiting device access.<br><br><b>--sysfs</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Mount a private <i>/sys</i> filesystem instance inside the cage, isolating system information.<br><br><b>--no-pty</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Do not allocate a pseudo-terminal (PTY) for the caged command, useful for non-interactive processes.<br><br><b>--noroot</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Prevent the user from gaining root privileges inside the cage, even if UID 0 is mapped.<br><br><b>--uid-map=<i>HOST_UID:CAGE_UID:COUNT</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Map a range of host UIDs to a range of UIDs inside the cage, enhancing user isolation.<br><br><b>--gid-map=<i>HOST_GID:CAGE_GID:COUNT</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Map a range of host GIDs to a range of GIDs inside the cage, enhancing group isolation.<br><br><b>--cap-add=<i>CAPABILITY</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Add a specific Linux capability to the caged process. Can be specified multiple times.<br><br><b>--cap-drop=<i>CAPABILITY</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Drop a specific Linux capability from the caged process, reducing potential attack surface.<br><br>


title: DESCRIPTION
content:
The <b>cage</b> command provides a lightweight sandboxing mechanism for running untrusted applications or processes in a restricted environment. It creates an isolated execution context, often referred to as a "cage," by leveraging Linux kernel features such as namespaces (mount, PID, user, network, UTS, IPC) and cgroups.<br><br>Unlike a simple <i>chroot</i>, <b>cage</b> offers more comprehensive isolation, including the ability to remap user and group IDs, prevent access to host filesystems and devices, set resource limits, and provide private instances of essential directories like <i>/proc</i> and <i>/dev</i>. This enhances security by limiting the potential damage an application can inflict if compromised, making it a valuable tool for running potentially malicious or buggy code safely.


title: CAVEATS
content:
Configuring <b>cage</b> for optimal security can be complex and requires a good understanding of Linux namespaces, capabilities, and filesystem permissions. Misconfigurations can inadvertently lead to security vulnerabilities or allow processes to break out of the cage.<br><br>While <b>cage</b> provides strong isolation, it is not a full virtualization solution like a virtual machine or a comprehensive container platform like Docker, which offer additional layers of isolation and orchestration. It is primarily designed for single-process sandboxing rather than hosting full operating system environments.


title: USE CASES
content:
<b>cage</b> is particularly useful for:<br>- Running untrusted scripts or binaries from unknown sources.<br>- Isolating build environments for compiling software.<br>- Providing a secure, minimal environment for specific network services.<br>- Testing applications in a controlled, isolated filesystem.


title: PREREQUISITES
content:
To use <b>cage</b> effectively, the underlying Linux kernel must support namespaces (mount, PID, user, network, IPC, UTS) and cgroups. While <b>cage</b> can often be run by non-root users (if configured with user namespace support), setting up complex cage environments, especially involving bind mounts or device mounts, often requires root privileges.


title: HISTORY
content:
The <b>cage</b> command is part of the <i>usermode</i> package, which emerged primarily within the Red Hat/Fedora ecosystem around the early 2000s. Its development was driven by the need for a lightweight, user-friendly sandboxing tool that could leverage evolving Linux kernel features like namespaces to isolate processes more effectively than a simple <i>chroot</i>.<br><br>It provides a more robust security boundary for running untrusted applications or creating isolated build environments without the overhead of full virtual machines. While not as widely known as modern container runtimes like Docker, <b>cage</b> remains a stable and effective tool for its specific niche in lightweight process isolation.


title: TLDR
content:
<b>Run an application</b>`cage [application]`<br><b>Give the application arguments</b>`cage -- [application] [arguments]`<br><b>Hide window [d]ecorations (this can lock you from accessing the terminal)</b>`cage -d [application]`<br><b>Allow [s]witching terminals with <Ctrl Alt F2></b>`cage -s [application]`<br><b>Display help</b>`cage -h`


title: PARAMETERS
content:
<b><b>-r</b> <i>&lt;file&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Read packets from the specified capture <i>file</i> (e.g., a PCAP file). This is commonly used for offline analysis.<br><br><b><b>-i</b> <i>&lt;interface&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Start a live packet capture on the specified network <i>interface</i> (e.g., eth0, wlan0). This requires appropriate permissions.<br><br><b><b>-D</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;List all available network interfaces that can be used for live capture and then exit. Useful for identifying interface names.<br><br><b><b>-f</b> <i>&lt;capture filter&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Apply a BPF-style <i>capture filter</i> to limit which packets are captured by the kernel. This filter is applied before packets are written to disk or processed by <b>tshark</b> (e.g., 'tcp port 80').<br><br><b><b>-Y</b> <i>&lt;display filter&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Apply an initial Wireshark-style <i>display filter</i> to the captured or loaded packets. This filter is applied after capture and dissection (e.g., 'http.request', 'ip.addr == 192.168.1.1').<br><br><b><b>-p</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Do not put the network interface into promiscuous mode during live capture. Only packets addressed to the host will be seen, potentially missing broadcast or other network traffic.<br><br><b><b>-s</b> <i>&lt;snaplen&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Set the snapshot length for packet capture to <i>snaplen</i> bytes. Only the first <i>snaplen</i> bytes of each packet are captured, which can reduce file size for large captures but might truncate packet data.<br><br><b><b>-l</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Start directly in live capture mode. This option is particularly useful for continuous real-time traffic monitoring, especially when operating over SSH where interactive control might be delayed.<br><br><b><b>--config</b> <i>&lt;dir&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specify an alternative configuration <i>directory</i> for <b>termshark</b> settings and history. By default, it uses a standard XDG configuration path.<br><br><b><b>--color-scheme</b> <i>&lt;scheme&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Set the UI color <i>scheme</i> (e.g., 'dark', 'light'). This allows users to customize the visual appearance to their preference or terminal background.<br><br>


title: DESCRIPTION
content:
<b>termshark</b> is a powerful, open-source terminal user interface (TUI) for <b>tshark</b>, the command-line packet analyzer that comes with Wireshark.<br><br>It provides a rich, interactive experience for network traffic analysis directly within your terminal, making it ideal for SSH sessions, remote servers, or environments where a graphical desktop is not available or desired. <b>termshark</b> can capture live network traffic or open existing PCAP files, presenting the data in a familiar three-pane layout similar to Wireshark: packet list, packet details, and packet bytes.<br><br>It supports display filters, search functionalities, and various navigation options, allowing users to efficiently inspect network protocols, troubleshoot connectivity issues, and analyze security incidents without leaving the command line. By leveraging the robust dissection capabilities of <b>tshark</b>, <b>termshark</b> offers deep protocol inspection in a lightweight, accessible format.


title: CAVEATS
content:
While powerful, <b>termshark</b> operates within the limitations of a terminal interface. It lacks the rich graphical features of Wireshark, such as complex statistics graphs or visual flow analysis. Mouse support may be limited depending on the terminal emulator. It requires <b>tshark</b> to be installed and accessible in the system's PATH. For very high-throughput networks, the performance can be constrained by terminal rendering speed and <b>tshark</b>'s processing capabilities, potentially leading to dropped packets if not properly configured.


title: DEPENDENCIES
content:
<b>termshark</b> is fundamentally dependent on <b>tshark</b>, which must be installed and accessible in your system's PATH. <b>tshark</b> is part of the Wireshark suite. Without <b>tshark</b>, <b>termshark</b> cannot function as it relies on <b>tshark</b> for all packet capture and dissection capabilities.


title: KEY BINDINGS
content:
The user interface of <b>termshark</b> largely mimics the key bindings and navigation paradigm of graphical Wireshark, making it intuitive for users already familiar with Wireshark. Common actions like navigating lists, applying filters, and inspecting packet details are performed using similar keyboard shortcuts.


title: HISTORY
content:
<b>termshark</b> was developed by Mark Ellzey to address the need for a full-featured network protocol analyzer that could run directly in a terminal. It emerged as a solution for scenarios where a graphical environment was unavailable, such as on remote servers accessed via SSH, or for users who preferred a command-line-centric workflow. The project began around 2018, leveraging the robust packet dissection engine of <b>tshark</b> to provide a Wireshark-like interactive experience without the graphical overhead, quickly gaining popularity among network administrators and security professionals.


title: TLDR
content:
<b>Monitor the default network interface</b>`sudo termshark`<br><b>Specify the interface to monitor</b>`sudo termshark [interface]`


title: PARAMETERS
content:
<b>up</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Starts or creates a new DevPod based on a configuration, making it ready for development.<br><br><b>down</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Stops a running DevPod, pausing its resources but not deleting it.<br><br><b>connect</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Connects to a running DevPod, typically opening it in an IDE or providing shell access.<br><br><b>delete</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Deletes one or more DevPods, freeing up all associated resources.<br><br><b>list</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Lists all existing DevPods and their current status across configured providers.<br><br><b>build</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Builds a custom DevPod image from a DevContainer configuration or Dockerfile, useful for pre-building.<br><br><b>inspect</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Provides detailed information and metadata about a specific DevPod.<br><br><b>provider</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Manages DevPod providers, allowing configuration of Kubernetes, Docker, or other backends.<br><br><b>--help</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays help information for the <b>devpod</b> command or a specific subcommand.<br><br><b>--version</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Prints the installed <b>devpod</b> client version.<br><br><b>--debug</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Enables verbose debug logging output for troubleshooting.<br><br><b>--provider <name></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the DevPod provider to use for the command (e.g., 'kubernetes', 'docker').<br><br>


title: DESCRIPTION
content:
<i>devpod</i> is an open-source command-line interface (CLI) tool designed to simplify the creation and management of remote development environments. Developed by Loft Labs, it enables developers to quickly spin up consistent, reproducible, and isolated workspaces in the cloud, on a local machine, or on a remote server.<br><br>Utilizing technologies like Kubernetes and Docker, <i>devpod</i> allows users to define their development environment using industry-standard configurations like <i>devcontainer.json</i> (familiar from VS Code Dev Containers) or a simple <i>Dockerfile</i>. This ensures that every team member works within an identical setup, eliminating "it works on my machine" issues and streamlining onboarding for new developers.<br><br><i>devpod</i> supports various providers, including local Docker, remote Kubernetes clusters (via <i>vcluster</i>), and SSH. It integrates seamlessly with popular IDEs and editors, allowing developers to connect to their remote workspace as if it were local. Its core philosophy revolves around providing ephemeral, on-demand development environments that can be started, stopped, and deleted as needed, optimizing resource usage and enhancing developer productivity.


title: CAVEATS
content:
<i>devpod</i> requires either Docker or a Kubernetes cluster to operate, as it leverages these technologies for environment isolation and resource management. It is not a standard Linux utility and must be installed separately. Users must define their environment using a <i>devcontainer.json</i> file or a <i>Dockerfile</i>, which requires some initial setup. Network connectivity is crucial for connecting to remote DevPods. While it aims for reproducibility, external dependencies not defined in the container might still lead to inconsistencies.


title: IDE INTEGRATION
content:
<i>devpod</i> is designed to integrate with popular Integrated Development Environments (IDEs) and code editors, such as VS Code. Once a DevPod is running, users can often connect to it directly from their IDE, enabling a seamless development experience where code execution, debugging, and terminal access occur remotely within the DevPod.


title: DEV CONTAINER SPECIFICATION
content:
A core feature of <i>devpod</i> is its support for the Dev Container Specification. This open standard allows developers to define a container-based development environment, including tools, runtimes, and dependencies, in a portable and reproducible manner using a <i>devcontainer.json</i> file. This ensures that the development setup is consistent for everyone using the project.


title: HISTORY
content:
<i>devpod</i> was developed by Loft Labs, a company known for its work in Kubernetes tooling, specifically <i>vcluster</i> (virtual Kubernetes clusters). It emerged from the growing need for standardized, ephemeral development environments in cloud-native workflows. The project gained traction in the open-source community, particularly with the rise of remote development and the adoption of Dev Containers as a common standard for defining development setups. Its development focuses on simplifying the onboarding experience for developers and ensuring environmental consistency across teams, building upon existing containerization and orchestration technologies.


title: TLDR
content:
<b>Add a provider such as Docker or Kubernetes</b>`devpod provider add [provider_name]`<br><b>List all available providers</b>`devpod provider list-available`<br><b>Start a workspace from a GitHub repository with a specific IDE</b>`devpod up [github.com/user/repo] [[-i|--ide]] [vscode]`<br><b>Start a workspace from a local directory</b>`devpod up [path/to/project]`<br><b>Recreate an existing workspace</b>`devpod up [workspace_name] [[-r|--recreate]]`<br><b>Reset a workspace to a clean state</b>`devpod up [workspace_name] [[-x|--reset]]`<br><b>Add a custom provider from a GitHub repository</b>`devpod provider add [org/provider-repo]`


title: TLDR
content:
<b>Create a virtual cluster in a specific namespace</b>`vcluster create [vcluster_name] [[-n|--namespace]] [namespace]`<br><b>Connect to a virtual cluster with a local port and insecure mode</b>`vcluster connect [vcluster_name] [[-n|--namespace]] [namespace] --local-port [port] --insecure`<br><b>List all virtual clusters</b>`vcluster list`<br><b>Delete a virtual cluster</b>`vcluster delete [vcluster_name]`<br><b>List platform-managed virtual clusters</b>`vcluster platform list`<br><b>Create a platform-managed virtual cluster</b>`vcluster platform create [vcluster_name] [[-n|--namespace]] [namespace]`<br><b>Connect to a platform-managed virtual cluster</b>`vcluster platform connect [vcluster_name] [[-n|--namespace]] [namespace]`<br><b>Delete a platform-managed virtual cluster</b>`vcluster platform delete [vcluster_name] [[-n|--namespace]] [namespace]`


title: SYNOPSIS
content:
<b>agg</b> [<i>OPTIONS</i>] [<i>FILE</i>...]<br><i>or</i><br><i>command</i> | <b>agg</b> [<i>OPTIONS</i>]


title: PARAMETERS
content:
<b>-g <i>FIELD</i>...</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies one or more fields to group data by. Records with identical values in these fields will be grouped together for aggregation.<br><br><b>-s <i>FIELD</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Calculates the sum of numerical values in the specified field for each group.<br><br><b>-a <i>FIELD</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Computes the average of numerical values in the specified field for each group.<br><br><b>-c <i>FIELD</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Counts the number of records within each group, optionally based on a specific field.<br><br><b>-m <i>FIELD</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Finds the minimum numerical value in the specified field for each group.<br><br><b>-M <i>FIELD</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Finds the maximum numerical value in the specified field for each group.<br><br><b>-o <i>FIELD</i>...</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the output order and inclusion of grouped fields and aggregated results.<br><br><b>-d <i>DELIMITER</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets the input and/or output field delimiter (e.g., ',' for CSV, '\t' for TSV). Defaults to whitespace.<br><br><b>-H</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Treats the first line of input as a header row, which is then processed separately or used for field naming in output.<br><br>


title: DESCRIPTION
content:
The <b>agg</b> command is not a standard, widely distributed utility found in most common Linux distributions. This analysis describes a <i>conceptual</i> command that would typically perform data aggregation tasks on structured text data, similar to the functionality provided by SQL's GROUP BY clause. If it existed, <b>agg</b> would likely be designed to process input (from files or standard input) and compute summary statistics based on specified grouping criteria. For example, it could sum numerical values, calculate averages, count occurrences, find minimums or maximums, or concatenate strings within groups of records that share common key values. This type of command would be invaluable for tasks such as generating reports, summarizing log files, analyzing datasets, and performing basic business intelligence directly from the command line. Its primary goal would be to transform detailed input data into a more concise, aggregated output, facilitating quicker insights and further analysis without requiring complex scripts or dedicated database systems. Users seeking such functionality typically rely on a combination of existing powerful text processing tools or specialized utilities designed for data manipulation.


title: CAVEATS
content:
The <b>agg</b> command is not a standard, universally available utility in common Linux distributions. This analysis describes a <i>conceptual</i> command that would perform data aggregation, based on the common meaning of 'agg' (aggregate). Users typically achieve similar functionality using combinations of standard tools like <b>awk</b>, <b>sort</b>, <b>uniq</b>, <b>cut</b>, <b>datamash</b>, or scripting languages like Python/Perl. Therefore, attempting to execute 'agg' on a typical Linux system will likely result in a 'command not found' error.


title: ACHIEVING DATA AGGREGATION IN LINUX
content:
Since a standard <b>agg</b> command is not available, users can achieve similar data aggregation results using a combination of powerful existing Linux utilities or specialized tools:<br><br><i>Command Line Tools</i>: For simple aggregations, tools like <b>sort</b> and <b>uniq -c</b> can count unique occurrences. For more complex numerical calculations (sums, averages), <b>awk</b> is highly versatile, allowing users to group data and perform calculations. The <b>datamash</b> utility is a dedicated tool specifically designed for various forms of numerical and textual data aggregation on tabular data.<br><br><i>Scripting Languages</i>: For highly complex aggregation logic, multi-step processes, or integration with other data sources, scripting languages such as Python or Perl are often employed. They offer robust data structures (like dictionaries/hashes) that are ideal for grouping and aggregating data programmatically.<br><br>Understanding the capabilities of these tools allows users to build powerful data processing pipelines on the Linux command line, effectively replacing the need for a dedicated 'agg' command.


title: HISTORY
content:
As <b>agg</b> is not a standard Linux command, it does not have a documented history of development or widespread usage in official repositories. The concept of 'aggregation' itself is fundamental to data processing and has been implemented in various forms across many tools and programming languages. While a dedicated 'agg' command might exist in specific, niche environments or as a custom script, it lacks a common lineage or evolutionary path within the broader Linux ecosystem.


title: TLDR
content:
<b>Create a GIF</b>`agg [path/to/demo.cast] [path/to/demo.gif]`<br><b>Create a GIF that is 80 columns wide and 25 rows in height</b>`agg --cols 80 --rows 25 [path/to/demo.cast] [path/to/demo.gif]`<br><b>Create a GIF with a font size of 24 pixels</b>`agg --font-size 24 [path/to/demo.cast] [path/to/demo.gif]`<br><b>Display help</b>`agg [[-h|--help]]`


title: SYNOPSIS
content:
The <b>loft</b> command serves as the primary interface for the loft platform, allowing users to manage development environments, virtual clusters, and project resources. It follows a subcommand-based structure.<br><br><b>Syntax:</b><br><I>loft</I> [<i>global options</i>] <I>command</I> [<i>command options</i>] [<i>arguments</i>]<br><I>loft</I> <I>command</I> --help<br><br><b>Common Commands:</b><br>&nbsp;&nbsp;<b>loft login</b> <I>&lt;server-url&gt;</I> [--access-key <I>&lt;key&gt;</I>]<br>&nbsp;&nbsp;<b>loft create space</b> <I>&lt;space-name&gt;</I><br>&nbsp;&nbsp;<b>loft use space</b> <I>&lt;space-name&gt;</I><br>&nbsp;&nbsp;<b>loft dev</b> [<i>options</i>] [-- <I>&lt;command-to-run&gt;</I>]<br>&nbsp;&nbsp;<b>loft connect</b> <I>&lt;vcluster-name&gt;</I> --port <I>&lt;local-port&gt;</I>:<I>&lt;remote-port&gt;</I><br>&nbsp;&nbsp;<b>loft get</b> [<i>type</i>] [<i>name</i>]<br>&nbsp;&nbsp;<b>loft delete</b> [<i>type</i>] [<i>name</i>]


title: PARAMETERS
content:
<b>--context <name></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the loft context to use for the command, overriding the default or current context.<br><br><b>--kube-context <name></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the Kubernetes context to use for operations that directly interact with a Kubernetes cluster.<br><br><b>--server <url></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Overrides the configured loft server URL for the current command execution.<br><br><b>--output <format></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets the output format for data retrieval commands (e.g., <I>json</I>, <I>yaml</I>, <I>table</I>).<br><br><b>--log-level <level></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Configures the verbosity of log output (e.g., <I>info</I>, <I>debug</I>, <I>warn</I>, <I>error</I>).<br><br><b>--help, -h</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays help information for the command or subcommand.<br><br>


title: DESCRIPTION
content:
The <b>loft</b> command-line interface (CLI) is the primary tool for interacting with the loft platform, a Kubernetes-native framework designed to provide self-service access to development environments for engineering teams. It enables developers to quickly create, manage, and share isolated <I>virtual clusters</I> or <I>spaces</I> on demand, abstracting away complex Kubernetes configurations. This significantly accelerates development workflows by providing instant access to disposable, production-like environments, reducing infrastructure costs, and improving compliance through centralized management. <b>loft</b> helps to eliminate cluster sprawl, streamline developer onboarding, and facilitate team collaboration by allowing developers to spin up dedicated environments without requiring direct administrative access to the underlying Kubernetes cluster. It integrates seamlessly with existing CI/CD pipelines and developer tools, making it an essential component for modern cloud-native development.


title: CAVEATS
content:
The <b>loft</b> CLI requires a running <b>loft</b> management server to function, as it primarily acts as a client for this platform. It is not a standalone Kubernetes cluster manager like <I>kubectl</I> but rather an orchestration layer designed to provide self-service environments on top of existing Kubernetes infrastructure. While it simplifies access and management of environments, certain advanced Kubernetes operations may still require direct <I>kubectl</I> usage. Its full capabilities are dependent on the features and configuration of the deployed <b>loft</b> platform.


title: CORE CONCEPTS
content:
<b>loft</b> introduces several key concepts to facilitate its self-service capabilities:<br><ul><li><I>Spaces</I>: Isolated, multi-tenant environments within a Kubernetes cluster, providing a dedicated namespace or a virtual cluster for each team or project.<br><li><I>Virtual Clusters</I>: Lightweight, high-performance Kubernetes clusters that run on top of an underlying host cluster, offering true isolation and administrative capabilities similar to a full cluster without the overhead.<br><li><I>Projects</I>: A way to group spaces, virtual clusters, and users, enabling centralized management of access control and resource quotas across different environments.


title: HISTORY
content:
The <b>loft</b> project emerged from the team behind <I>devspace.sh</I>, initially focusing on virtual clusters as a solution to provide isolated development environments within shared Kubernetes clusters. Over time, its scope expanded to become a comprehensive self-service platform for managing developer access, projects, and resources across multiple Kubernetes clusters. It is an actively developed open-source project, with a strong focus on simplifying Kubernetes for developers and enabling efficient team collaboration. Its development continues to be driven by the needs of cloud-native development workflows, aiming to bridge the gap between developers and complex Kubernetes infrastructure.


title: TLDR
content:
<b>Install or upgrade Loft in the current Kubernetes cluster</b>`loft start`<br><b>Authenticate to a remote Loft instance</b>`loft login [https://loft.example.com]`<br><b>Create a virtual cluster with a specific space and cluster</b>`loft create vcluster [vcluster_name] [[-s|--space]] [space_name] [[-c|--cluster]] [cluster_name]`<br><b>List all virtual clusters</b>`loft list vclusters`<br><b>Switch context to a specific virtual cluster</b>`loft use vcluster [vcluster_name]`<br><b>Delete a virtual cluster</b>`loft delete vcluster [vcluster_name]`<br><b>Show the current Loft username</b>`loft vars username`<br><b>Uninstall Loft from the cluster</b>`loft uninstall`


title: SYNOPSIS
content:
<b>mdk4</b> <i>&lt;interface&gt; &lt;mode&gt;</i> [<i>&lt;mode_options&gt;</i>]<br><b>mdk4</b> [<i>&lt;options&gt;</i>] <i>&lt;interface&gt; &lt;mode&gt;</i> [<i>&lt;mode_options&gt;</i>]<br>Example: <b>mdk4</b> <i>wlan0mon</i> <b>d</b> <i>-a 00:11:22:33:44:55 -c 6</i>


title: PARAMETERS
content:
<b><i>&lt;interface&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;The wireless interface to use, which must be in monitor mode (e.g., <i>wlan0mon</i>).<br><br><b><i>&lt;mode&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the attack mode. Common modes include:<br><b>b</b>: Beacon Flood Mode<br><b>a</b>: Authentication Flood Mode<br><b>d</b>: Deauthentication / Disassociation Flood Mode<br><b>p</b>: Probe Request Flood Mode<br><b>e</b>: EAPOL-Start Flood Mode (for WPA/WPA2)<br><b>w</b>: WPA KICK (WPA Deauthentication)<br><b>f</b>: MAC Filter Test Mode<br><br><b><i>-a &lt;ap_mac&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Target Access Point MAC address (e.g., in Deauth Mode).<br><br><b><i>-t &lt;target_mac&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Target client MAC address (e.g., in Deauth Mode).<br><br><b><i>-c &lt;channel&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Set the channel to operate on.<br><br><b><i>-s &lt;pps&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Set the attack speed in packets per second (pps).<br><br><b><i>-D</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Do not deauthenticate/disassociate yourself when targeting a specific client.<br><br><b><i>-h</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Show help message and exit.<br><br><b><i>-L</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;List available wireless devices and their capabilities.<br><br>


title: DESCRIPTION
content:
<i>mdk4</i> is a powerful and versatile command-line tool designed for testing the security and stability of wireless networks. It is the successor to <i>mdk3</i>, offering a wide range of attack modes for various wireless protocols, primarily focusing on Wi-Fi (802.11). <i>mdk4</i> can perform denial-of-service (DoS) attacks by flooding networks with various types of packets, such as beacon frames, authentication requests, or deauthentication/disassociation frames. It can also be used for legitimate penetration testing and security auditing to identify vulnerabilities in access points or client devices. The tool requires a wireless network adapter that supports monitor mode and packet injection. Due to its potential for disruption, <i>mdk4</i> should only be used on networks for which you have explicit permission to test.


title: CAVEATS
content:
Using <i>mdk4</i> against networks you do not own or have explicit permission to test is illegal and unethical. It can cause significant disruption to wireless services and is detectable. Ensure you comply with all local laws and regulations before using this tool. A wireless adapter capable of monitor mode and packet injection is mandatory.


title: PREREQUISITES
content:
Before using <i>mdk4</i>, ensure your wireless network adapter supports monitor mode and packet injection. Tools like <i>airmon-ng</i> (part of the <i>aircrack-ng</i> suite) are often used to put the interface into the required monitor mode.


title: LEGAL AND ETHICAL CONSIDERATIONS
content:
<i>mdk4</i> is a powerful tool. Misuse can lead to severe legal consequences. Always obtain explicit written permission from the network owner before performing any tests. Use it responsibly for educational or authorized security auditing purposes only.


title: HISTORY
content:
<i>mdk4</i> emerged as the successor to <i>mdk3</i>, a well-known wireless network testing tool. It was developed to address limitations and introduce new attack vectors, particularly for modern Wi-Fi standards. Its development is rooted in the open-source community focused on wireless security and penetration testing, aiming to provide robust tools for ethical hacking and security research.


title: SYNOPSIS
content:
<b><I>pokeget</I></b> <I>[OPTIONS]</I> <I>[POKEMON_NAME_OR_ID]</I><br><b><I>pokeget</I></b> <I>-l</I> <I>[--type TYPE]</I>


title: PARAMETERS
content:
<b>POKEMON_NAME_OR_ID</b><br>&nbsp;&nbsp;&nbsp;&nbsp;The name or National Pokédex ID of the Pokémon to retrieve information for. Case-insensitive for names.<br><br><b>-f, --format <FORMAT></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specify the output format. Supported formats include <I>text</I> (default, human-readable summary), <I>json</I> (raw API response), and <I>brief</I> (concise one-liner).<br><br><b>-v, --verbose</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Display more detailed information, potentially including hidden abilities, more move details, or full Pokédex entries.<br><br><b>-l, --list</b><br>&nbsp;&nbsp;&nbsp;&nbsp;List all available Pokémon by name and ID. Can be combined with <I>--type</I> to filter.<br><br><b>-t, --type <TYPE></b><br>&nbsp;&nbsp;&nbsp;&nbsp;When used with <I>-l</I>, filters the list to only show Pokémon of the specified type (e.g., "fire", "water").<br><br><b>-s, --stats-only</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Output only the base stats of the specified Pokémon.<br><br><b>-a, --abilities-only</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Output only the abilities of the specified Pokémon.<br><br><b>-h, --help</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Display a help message and exit.<br><br>


title: DESCRIPTION
content:
<I>pokeget</I> is a convenient command-line utility designed for Pokémon enthusiasts and developers alike, enabling quick retrieval of comprehensive data for any Pokémon. By leveraging a public API (hypothetical), it provides instant access to vital statistics such as types, abilities, base stats, moves, and even flavor text. Whether you're planning your next team, exploring Pokémon lore, or integrating data into a script, <I>pokeget</I> streamlines the process, eliminating the need to browse external websites. It supports lookup by both Pokémon name and National Pokédex ID, and offers various output formats to suit different needs, from a concise summary to a full JSON representation. This tool aims to bring the vast world of Pokémon data right into your command-line environment, making information access fast and efficient.


title: CAVEATS
content:
<I>pokeget</I> is a hypothetical command-line tool. It is not a standard Linux command or a widely distributed utility. To use a command like this, it would need to be specifically developed, installed, and configured on your system, likely relying on an external API for Pokémon data (e.g., PokeAPI). Its functionality, options, and data sources would depend entirely on its implementation. Requires an active internet connection to fetch data.


title: EXAMPLES
content:
Here are some common usage examples for <I>pokeget</I>:<br><br><b>1. Get information for a specific Pokémon (e.g., Pikachu):</b><br><b><I>pokeget</I></b> pikachu<br><br><b>2. Get information by National Pokédex ID (e.g., Bulbasaur):</b><br><b><I>pokeget</I></b> 001<br><br><b>3. Output data in JSON format for scripting:</b><br><b><I>pokeget</I></b> charizard <b><I>--format</I></b> json | <b><I>jq</I></b> '.abilities'<br><br><b>4. List all Fire-type Pokémon:</b><br><b><I>pokeget</I></b> <b><I>--list</I></b> <b><I>--type</I></b> fire<br><br><b>5. Show only stats for a Pokémon:</b><br><b><I>pokeget</I></b> eevee <b><I>--stats-only</I></b>


title: EXIT STATUS
content:
<I>pokeget</I> typically exits with one of the following status codes:<br><b>0</b>: Success. The command executed without errors.<br><b>1</b>: General error. Could be a network issue, API error, or malformed request.<br><b>2</b>: Invalid argument or option. The provided Pokémon name/ID was not found or an option was used incorrectly.


title: HISTORY
content:
The concept of <I>pokeget</I> likely originates from the desire of Pokémon fans and developers for a quick, command-line interface to access Pokémon data without relying on graphical browsers. Such a tool would typically be a community-driven project, often written in scripting languages like Python or Node.js, making use of freely available Pokémon API services. Its development would be iterative, adding new features like filtering, specific data points, and improved output formatting based on user demand, evolving from simple data retrieval to a more comprehensive Pokédex utility for the terminal.


title: SEE ALSO
content:
<I>curl(1)</I> (for fetching data from web APIs), <I>jq(1)</I> (for processing JSON data), <I>grep(1)</I> (for filtering output), <I>less(1)</I> (for viewing paginated output)


title: PARAMETERS
content:
<b><I>--help</I>, <I>-h</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;<I>Show help message for the Quarto command or a specific subcommand.</I><br><br><b><I>--version</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;<I>Display the installed Quarto version.</I><br><br><b><I>--log-level &lt;level&gt;</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;<I>Specify the minimum log level to display (e.g., info, warn, error, debug).</I><br><br><b><I>--log-format &lt;format&gt;</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;<I>Specify the log output format (e.g., default, json).</I><br><br><b><I>--quiet</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;<I>Suppress all console output except for critical errors.</I><br><br><b><I>--no-colors</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;<I>Disable colored output in the console.</I><br><br>


title: DESCRIPTION
content:
<I>Quarto is an open-source scientific and technical publishing system built on Pandoc. It allows users to create high-quality articles, presentations, websites, books, and interactive documents from various input formats, including Markdown, Jupyter notebooks, R Markdown, and Observable JS.<br><br>Quarto is designed to be language-agnostic, supporting Python, R, Julia, and Observable JS code execution within documents, making it a versatile tool for data scientists, researchers, and technical writers. It simplifies the process of integrating code, narrative, and rich media, outputting to a wide range of formats such as HTML, PDF, Microsoft Word, EPUB, and more.<br><br>Quarto provides a unified interface for authoring and rendering, aiming to make reproducible research and reporting accessible and efficient across different computing environments and tools like VS Code, RStudio, and Jupyter Lab.</I>


title: CAVEATS
content:
<I>Quarto is a comprehensive system with a rich set of features. While its basic usage is straightforward, fully leveraging its capabilities often requires understanding its YAML front matter for document configuration, specific options for its numerous subcommands (e.g., <B>render</B>, <B>preview</B>, <B>publish</B>), and its integration with various language engines (Python, R, Julia).<br><br>Generating certain output formats (e.g., PDF) may require external dependencies like a TeX distribution (e.g., TinyTeX, TeX Live). Users should consult the official Quarto documentation for detailed guidance on advanced features and troubleshooting dependencies.</I>


title: <B>CORE SUBCOMMANDS</B>
content:
<I>Quarto operates primarily through subcommands. The most frequently used include <B>quarto render</B> (to process and output a document), <B>quarto preview</B> (to render and display a document in a browser with live-reload), <B>quarto publish</B> (to deploy content to various hosting services), <B>quarto create</B> (to scaffold new projects or documents), and <B>quarto check</B> (to diagnose installation issues).</I>


title: <B>YAML FRONT MATTER</B>
content:
<I>Document-specific configuration in Quarto is typically managed using YAML front matter at the beginning of source files. This allows users to control output formats, themes, table of contents, citations, and many other aspects of the rendered document in a declarative way.</I>


title: <B>IDE INTEGRATION</B>
content:
<I>Quarto is deeply integrated with popular IDEs such as Posit's RStudio, VS Code (via an extension), and Jupyter Lab (via an extension), providing seamless authoring, rendering, and previewing experiences.</I>


title: HISTORY
content:
<I>Quarto was developed by Posit (formerly RStudio) and officially released in 2022. It represents an evolution of the popular R Markdown framework, aiming to provide a more universal, language-agnostic, and robust publishing system. While R Markdown was primarily focused on R, Quarto extends its capabilities to Python, Julia, and Observable JS, leveraging the power of Pandoc for document conversion. Its development was driven by the goal of creating a unified standard for reproducible computational documents across various programming languages and integrated development environments.</I>


title: PARAMETERS
content:
<b>-i</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Ignores the first word of the question for sorting purposes. This is useful for lists where articles (like 'The' or 'A') might affect alphabetical order.<br><br><b>-t</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Enables test mode, which prints both the question and its answer immediately, followed by a bell. This is helpful for debugging new or modified data files.<br><br><b>-r</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Reverses the question and answer. The original answer becomes the question, and the original question becomes the answer, allowing for 'backwards' knowledge testing.<br><br><b>-h</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Activates hard mode. If an answer is incorrect, the question is repeated in a much briefer format, rather than cycling through similar questions.<br><br><b>-n</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Disables randomization. Questions are presented in the exact order they appear in the specified data file(s).<br><br><b>-p</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets the scoring to percentage mode. The final score displays the percentage of correct answers achieved on the first attempt.<br><br><b>-l num</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Limits the number of questions asked during the session to 'num'.<br><br><b>file ...</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies one or more custom data files to be used for questions. If no files are specified, the default data file is used.<br><br>


title: DESCRIPTION
content:
The <i>quiz</i> command is an interactive command-line utility designed to test a user's knowledge on various subjects. It reads questions and answers from specified data files, or a default file like <b>/usr/share/games/quiz/quiz.k</b>. The program presents questions one by one, awaiting the user's input. If an answer is incorrect, <i>quiz</i> may re-present a briefer form of the same question or a different question covering similar material until the correct answer is provided or the user opts to skip.<br><br>A score is maintained throughout the session, and at the end, the percentage of correct answers is displayed. Users can supply their own data files, which consist of lines with a question and its answer separated by a tab. Lines beginning with '#' are treated as comments, and empty lines are ignored.


title: CAVEATS
content:
The default data file (<b>/usr/share/games/quiz/quiz.k</b>) is typically part of the <i>bsdgames</i> package and might not be installed by default on all Linux distributions. Custom data files must adhere to a simple format: question and answer separated by a tab.


title: FILES
content:
<b>/usr/share/games/quiz/quiz.k</b><br>This is the default data file used by the <i>quiz</i> command if no specific data files are provided as arguments.


title: AUTHORS
content:
The original author of the <i>quiz</i> command is listed as unknown. The version distributed as part of <i>bsdgames</i> was rewritten by David F. Hirst.


title: HISTORY
content:
A <i>quiz</i> command first appeared in Version 6 AT&T UNIX. The version commonly found in <i>bsdgames</i> on modern systems is a complete rewrite by David F. Hirst.


title: SYNOPSIS
content:
<b>rc-status</b> [<i>-a</i>|<i>--all</i>] [<i>-c</i>|<i>--crashed</i>] [<i>-f &lt;format&gt;</i>|<i>--format=&lt;format&gt;</i>] [<i>-l</i>|<i>--list-runlevels</i>] [<i>-r &lt;runlevel&gt;</i>|<i>--runlevel=&lt;runlevel&gt;</i>] [<i>-s</i>|<i>--services-only</i>] [<i>-v</i>|<i>--verbose</i>]


title: PARAMETERS
content:
<b><i>-a</i>, <i>--all</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays the status of services across all defined runlevels on the system, not just the currently active ones.<br><br><b><i>-c</i>, <i>--crashed</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Filters the output to show only services that are currently in a crashed state, indicating an unexpected termination.<br><br><b><i>-f &lt;format&gt;</i>, <i>--format=&lt;format&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the output format for the status information. Common formats include 'json', 'xml', 'csv', or 'bare' for scripting purposes.<br><br><b><i>-l</i>, <i>--list-runlevels</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Lists all available runlevels configured on the system, which define different sets of services for various operating modes.<br><br><b><i>-r &lt;runlevel&gt;</i>, <i>--runlevel=&lt;runlevel&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays the status of services only within the specified <i>&lt;runlevel&gt;</i>, such as 'boot', 'sysinit', or 'default'.<br><br><b><i>-s</i>, <i>--services-only</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Suppresses the display of runlevel headers, showing only the services and their respective statuses in a more compact list.<br><br><b><i>-v</i>, <i>--verbose</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Provides more detailed information about each service, often including its process ID (PID) if it's running.<br><br>


title: DESCRIPTION
content:
The <i>rc-status</i> command is a fundamental utility within the OpenRC init system, designed to provide a comprehensive overview of the current state of services managed by OpenRC. It helps system administrators monitor which services are running, stopped, or in various other states such as crashed, inactive, or hotplugged. By default, it categorizes services by their respective runlevels (e.g., boot, sysinit, default), offering a structured view of the system's operational services. The output is typically color-coded to visually distinguish service states, making it an indispensable tool for quick health checks and initial troubleshooting on OpenRC-based Linux distributions like Gentoo or Alpine Linux. It offers various options to filter the display, such as showing only crashed services, all runlevels, or a specific runlevel.


title: CAVEATS
content:
The <i>rc-status</i> command is specific to systems utilizing the OpenRC init system. It will not function on distributions that use other init systems like systemd (e.g., Ubuntu, Fedora, Debian) or SysVinit (older distributions). Compatibility with specific format options (e.g., 'json') might vary depending on the OpenRC version installed.


title: OUTPUT COLOR CODING
content:
The default output of <i>rc-status</i> employs color coding for rapid visual assessment:<br><i><b>Green</b></i>: Service is running/started.<br><i><b>Red</b></i>: Service is stopped or crashed.<br><i><b>Yellow</b></i>: Service is inactive, hotplugged, or in an otherwise non-running but not errored state.<br><i><b>White/Gray</b></i>: Service is undefined or unknown.


title: HISTORY
content:
<i>rc-status</i> is an integral part of OpenRC, an init system initially developed for Gentoo Linux as an alternative to the traditional SysVinit scripts. OpenRC aimed to provide a more modular, parallel, and dependency-aware service management framework. <i>rc-status</i> has been a core component since OpenRC's inception, providing users and administrators with a clear, real-time snapshot of the system's running services, embodying OpenRC's philosophy of transparency and control over system processes.


title: SYNOPSIS
content:
<b>readarray</b> [<i>-d delim</i>] [<i>-n count</i>] [<i>-O origin</i>] [<i>-s start</i>] [<i>-t</i>] [<i>-u fd</i>] [<i>array_name</i>]


title: PARAMETERS
content:
<b><i>-d delim</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies a delimiter character for lines. If <i>delim</i> is a null string, the line is terminated by the first null character rather than newline.<br><br><b><i>-n count</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Reads at most <i>count</i> lines. If <i>count</i> is 0, all lines are read.<br><br><b><i>-O origin</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Starts assigning to <i>array_name</i> at index <i>origin</i>. Defaults to 0. If <i>origin</i> is less than 0, it is treated as 0.<br><br><b><i>-s start</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Skips the first <i>start</i> lines read from the input. If <i>start</i> is less than 0, it is treated as 0.<br><br><b><i>-t</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Removes the trailing newline character from each line read. This is useful for preventing empty last elements or unwanted newlines.<br><br><b><i>-u fd</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Reads lines from the file descriptor <i>fd</i> instead of standard input. If <i>fd</i> is omitted, 0 (stdin) is used.<br><br><b><i>array_name</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;The name of the indexed array variable to be populated. If omitted, the default array <i>MAPFILE</i> is used.<br><br>


title: DESCRIPTION
content:
<i>readarray</i>, also known as <i>mapfile</i>, is a powerful Bash built-in command designed to read lines from standard input or a specified file descriptor directly into an indexed array variable. Each complete line read becomes a distinct element in the array. This command offers a highly efficient alternative to traditional line-by-line processing loops, such as <code>while read</code>, especially when dealing with large volumes of data.<br><br>It provides options to control how lines are read, allowing users to skip a specified number of initial lines, limit the total number of lines read, or remove trailing newline characters from each element. Furthermore, it enables the specification of the array's starting index, which can be useful for advanced array manipulation. By simplifying the process of ingesting data into arrays, <i>readarray</i> streamlines scripting tasks that involve list processing, configuration file parsing, or log analysis.


title: CAVEATS
content:
It is a <b>Bash built-in</b> command, not a standalone executable found in <code>/bin</code> or <code>/usr/bin</code>.<br><br><i>readarray</i> is an <b>alias</b> for the <i>mapfile</i> built-in command in Bash. Their functionalities are identical.<br><br>Primarily designed for <b>indexed arrays</b>; it does not directly support populating associative arrays.<br><br>Behavior and available options may vary slightly across different <b>Bash versions</b>. Ensure your Bash version supports the desired options.


title: EFFICIENCY
content:
<i>readarray</i> (or <i>mapfile</i>) is significantly faster than a <code>while read</code> loop for reading large files into an array. This performance gain stems from its nature as a compiled Bash built-in, which optimizes the input/output operations.


title: DEFAULT ARRAY VARIABLE
content:
If no <i>array_name</i> is specified, <i>readarray</i> populates a default array variable named <i>MAPFILE</i>. This can be directly accessed like any other array, e.g., <code>${MAPFILE[0]}</code>.


title: COMMON USE CASES
content:
<i>readarray</i> is commonly used for tasks such as parsing configuration files, processing line-oriented log data, handling lists of items from external commands, and general data manipulation where each line represents a distinct record.


title: HISTORY
content:
The <i>mapfile</i> built-in command was introduced in <b>Bash 4.0</b> as a more efficient method for reading data into arrays than traditional loops. The <i>readarray</i> alias was subsequently introduced in <b>Bash 4.3</b> (though some sources mention 4.2), providing a more intuitive and memorable name for the same functionality. Its development aimed to optimize input processing for large files and datasets, addressing performance bottlenecks encountered with older scripting idioms.


title: PARAMETERS
content:
<b><b>dev=</b><i>device</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the SCSI device or device alias (e.g., <i>/dev/sr0</i>, <i>0,0,0</i>).<br><br><b><b>f=</b><i>file</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the output file for the read data. Use <i>-</i> for standard output.<br><br><b><b>sectors=</b><i>N</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Reads <i>N</i> sectors from the disc. Also recognized as <b>size=</b><i>N</i>.<br><br><b><b>start=</b><i>N</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Starts reading from sector <i>N</i>.<br><br><b><b>audio</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Instructs <b>readcd</b> to read audio tracks (CDDA) instead of data tracks.<br><br><b><b>data</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Instructs <b>readcd</b> to read data tracks (default behavior).<br><br><b><b>speed=</b><i>N</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets the reading speed of the drive to <i>N</i>x.<br><br><b><b>noerror</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Continues reading even if read errors are encountered, attempting to skip bad blocks. Useful for damaged media.<br><br><b><b>retries=</b><i>N</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the number of times to retry reading a bad block (default is 0).<br><br><b><b>cuefile=</b><i>file</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Creates a CUE sheet file that describes the disc's layout and tracks.<br><br><b><b>dummy</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Performs a test read without actually writing data to the output file or disc.<br><br><b><b>verbose</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Increases the verbosity of the output, showing more details about the operation progress.<br><br><b><b>debug</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Activates debug output, providing highly detailed information for troubleshooting.<br><br><b><b>timeout=</b><i>N</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets the SCSI command timeout in seconds.<br><br><b><b>ts=</b><i>sectorsize</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets the target sector size for reading (e.g., 2048 bytes for data, 2352 bytes for audio).<br><br>


title: DESCRIPTION
content:
The <b>readcd</b> command is a versatile utility used for reading data and audio tracks from CD-ROM, DVD-ROM, and BD-ROM media. It is part of the `cdrtools` (or `wodim`) software suite, which provides comprehensive tools for disc mastering. Unlike simpler commands like `dd`, <b>readcd</b> offers advanced capabilities for low-level disc access, making it particularly useful for creating exact ISO images, extracting audio tracks (CDDA), and attempting data recovery from physically damaged or scratched discs. It supports various block sizes, error handling mechanisms, and precise control over the reading process, including specifying start sectors, total sectors, and read speed. This command is often employed when a more robust and granular approach to disc reading is required beyond standard filesystem mounting or basic imaging utilities.


title: CAVEATS
content:
<b>readcd</b> typically requires direct SCSI access to the optical drive, which might necessitate elevated permissions (e.g., running as root or having appropriate udev rules). While powerful for data recovery, it cannot bypass strong copy protection mechanisms, and its success on severely damaged media depends on the extent and type of damage. For simple ISO imaging of healthy discs, the <b>dd</b> command might be a more straightforward alternative. Be aware that different Linux distributions might package `readcd` as part of the `cdrtools` suite or its `wodim` fork, which could lead to minor behavioral differences.


title: HISTORY
content:
<b>readcd</b> is an integral part of the `cdrtools` suite, originally developed by Joerg Schilling. This suite was pioneering in providing robust CD/DVD burning and reading capabilities for Unix-like operating systems, with its development beginning in the mid-1990s. The core functionality of `readcd`, enabling low-level disc access and comprehensive error handling, has remained consistent. Due to licensing debates (specifically, the CDDL license used by `cdrtools` being incompatible with the GPL license preferred by many Linux distributions), forks like `wodim` (WOrk-aLike DIsk Mastering) were created and adopted by some distributions. Despite these changes, <b>readcd</b> has remained a crucial tool for specialized tasks such as audio extraction and data forensics, long after optical media became less common for general data storage.


title: PARAMETERS
content:
<b>-a, --all</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays all available information from the ELF file, a comprehensive overview.<br><br><b>-h, --file-header</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays the ELF file header information, including magic number, architecture, and entry point.<br><br><b>-l, --program-headers, --segments</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays the program headers (segments) of the ELF file, which describe how the file is mapped into memory by the system loader.<br><br><b>-S, --section-headers, --sections</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays the section headers of the ELF file, detailing various logical sections like code, data, symbol tables, and debugging information.<br><br><b>-s, --symbols, --syms</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays the symbol table entries, listing functions and variables defined or referenced by the ELF file. Use <b>-D</b> for dynamic symbols only.<br><br><b>-d, --dynamic</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays the dynamic section, which contains information crucial for dynamic linking (e.g., needed shared libraries, symbol references for runtime resolution).<br><br><b>-r, --relocs</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays the relocation entries, which specify how symbol references in the code or data need to be adjusted at load time by the dynamic linker.<br><br><b>-n, --notes</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays the notes section, often used for specific system or application-related information, such as build IDs or core dump details.<br><br><b>-x <section_name_or_index>, --hex-dump=<section_name_or_index></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Dumps the specified section's content in hexadecimal format. Useful for raw data inspection of any section by name or index.<br><br><b>-p <section_name_or_index>, --string-dump=<section_name_or_index></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Dumps the specified section's content as printable strings. Primarily useful for inspecting string tables like <i>.strtab</i> or <i>.dynstr</i>.<br><br><b>--debug-dump=<option></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Dumps various kinds of debugging information (e.g., <i>info</i>, <i>line</i>, <i>frames</i>) present in the ELF file, typically in DWARF format.<br><br><b>-w, --wide</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Prevents truncation of output lines, providing a wider view of information, which is useful for long symbol names or complex paths.<br><br>


title: DESCRIPTION
content:
<i>readelf</i> is a command-line utility used to display information about files in the <b>ELF</b> (Executable and Linkable Format) format. ELF is a standard binary file format used for executables, object code, shared libraries, and core dumps on various Unix-like operating systems, including Linux. Unlike tools like <i>objdump</i>, <i>readelf</i> focuses purely on the structure and content of the ELF file itself, without disassembling the code. It provides a detailed, human-readable representation of various sections and headers within an ELF file, such as the ELF header, program headers, section headers, symbol tables, relocation entries, and dynamic sections. This makes <i>readelf</i> an invaluable tool for developers, system administrators, and security researchers who need to inspect the low-level details of compiled binaries, debug linking issues, or analyze malicious code. It's particularly useful for understanding how a binary is laid out, what libraries it depends on, and what symbols it exports or imports.


title: CAVEATS
content:
<i>readelf</i> focuses purely on the structure of ELF files and does not perform code disassembly like <i>objdump</i>. Its output can be very verbose, especially when using the <b>-a</b> option or debugging flags, often requiring further processing with tools like <i>grep</i> or <i>less</i>. Interpreting the output requires a basic understanding of the ELF file format, including concepts like sections, segments, symbol tables, and relocation entries. While generally robust, it might struggle with severely malformed or non-standard ELF binaries.


title: COMMON USE CASES
content:
<i>readelf</i> is frequently used to:<br><b>&bull;</b> Inspect the ELF header to determine the file type, architecture, and entry point.<br><b>&bull;</b> Examine program headers to understand memory segments and their permissions for loading.<br><b>&bull;</b> View section headers to locate specific code, data, or debug sections within the file.<br><b>&bull;</b> Analyze symbol tables (using <b>-s</b>) to find exported and imported functions or variables, crucial for linking and debugging.<br><b>&bull;</b> Debug linking issues by inspecting dynamic sections (using <b>-d</b>) and relocation entries (using <b>-r</b>).<br><b>&bull;</b> Perform security analysis by identifying unusual sections, packed binaries, or suspicious library dependencies.


title: HISTORY
content:
<i>readelf</i> is an integral component of the <b>GNU Binutils</b> package, a foundational collection of binary utilities for Unix-like operating systems. Developed and maintained by the GNU Project, Binutils provides essential tools for compilers, linkers, and debuggers. <i>readelf</i>'s evolution has paralleled the widespread adoption of the ELF standard across various architectures, becoming a stable and indispensable utility for inspecting ELF binaries. Unlike its sibling tool <i>objdump</i>, <i>readelf</i> was specifically designed to focus on displaying the raw structural information of ELF files without attempting to disassemble code, providing a clear and precise view of the file's layout and metadata.


title: PARAMETERS
content:
<b><B>--headers</B>, <B>-H</B></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays the DOS, PE, COFF, and optional headers of the PE file.<br><br><b><B>--sections</B>, <B>-S</B></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Shows information about the section headers and their characteristics.<br><br><b><B>--imports</B>, <B>-i</B></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Lists the imported functions and the DLLs they are imported from.<br><br><b><B>--exports</B>, <B>-e</B></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays the functions exported by the module, including their names and addresses.<br><br><b><B>--resources</B>, <B>-r</B></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Shows information about the resource directory, including embedded icons, strings, and other data.<br><br><b><B>--debug</B>, <B>-d</B></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays the debug directory entries within the PE file.<br><br><b><B>--relocs</B>, <B>-R</B></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Lists the base relocation entries, which are used for adjusting addresses when the module is loaded at a different base address.<br><br><b><B>--all</B>, <B>-a</B></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays all available information about the PE file. This provides the most comprehensive output.<br><br><b><B>--version</B>, <B>-V</B></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Shows the version information for the <b>readpe</b> utility.<br><br><b><B>--help</B>, <B>-h</B></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays a help message with available options and their usage.<br><br>


title: DESCRIPTION
content:
<b>readpe</b> is a command-line utility used for displaying information about Portable Executable (PE) files. PE files are the standard executable file format for Windows operating systems, used for EXEs, DLLs, SYS files, and other components.<br><br>Similar to how <b>readelf</b> is used to analyze ELF (Executable and Linkable Format) files on Linux, <b>readpe</b> provides a detailed breakdown of various structures within a PE file. This includes headers (DOS, PE, COFF, Optional), section tables, import and export directories, resource sections, debug information, and relocation tables.<br><br>It's an invaluable tool for reverse engineering, malware analysis, or simply understanding the internal layout of Windows binaries on a Linux system, without needing a Windows environment. By parsing the PE structure, <b>readpe</b> helps developers and security researchers examine dependencies, functions, and data within these binaries.


title: CAVEATS
content:
<b>readpe</b> is primarily found as part of cross-compilation toolchains like <I>MinGW-w64</I> on Linux and might not be installed by default on all distributions. While it parses PE files, it does not execute them or interact with Windows APIs directly. Its output can be quite verbose, especially with the <B>--all</B> option, requiring piping to <I>less</I> or redirecting to a file for easier analysis.


title: COMMON USE CASES
content:
<br><b>Malware Analysis:</b> <br>Used to quickly identify imported APIs, suspicious sections, or embedded resources in PE files, aiding in threat intelligence and incident response.<br><br><b>Cross-Platform Development:</b> <br>Helps verify the structure and dependencies of PE binaries compiled on Linux before deploying them to Windows environments.<br><br><b>Reverse Engineering:</b> <br>Allows security researchers and developers to understand the file layout, entry points, and dependencies of proprietary Windows applications or libraries.


title: INSTALLATION (EXAMPLES)
content:
<b>readpe</b> is usually part of <I>mingw-w64-tools</I> or <I>mingw-w64-binutils</I> packages.<br><br><b>Debian/Ubuntu:</b> <br><I>sudo apt install mingw-w64-tools</I><br><br><b>Fedora:</b> <br><I>sudo dnf install mingw-w64-binutils</I><br><br><b>Arch Linux:</b> <br><I>sudo pacman -S mingw-w64-binutils</I>


title: HISTORY
content:
<b>readpe</b> is typically distributed as part of the <I>GNU Binutils</I> project or related cross-compilation toolchains like <I>MinGW-w64</I>, which aim to provide a complete development environment for Windows targets on Unix-like systems. Its development closely parallels the need for Linux users to inspect and work with Windows binaries without relying on Windows-native tools, especially crucial in cross-development, security analysis, and reverse engineering contexts.


title: SYNOPSIS
content:
<b>reflex</b> [<i>options</i>] <i>&lt;command&gt;</i><br>Example: <i>reflex -r '\.go$' go run main.go</i><br>Example: <i>reflex -s -d 500ms -e 'vendor' make</i>


title: PARAMETERS
content:
<b>-A <i>&lt;path&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Add an additional <i>directory path</i> to watch. This option can be specified multiple times to watch several distinct directories. By default, <b>reflex</b> watches the current working directory.<br><br><b>-c</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Clear the terminal screen before each command execution, providing a clean output for every run.<br><br><b>-d <i>&lt;duration&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Set a <i>debounce duration</i> (e.g., <code>500ms</code>, <code>1s</code>) to wait for file changes to settle before re-executing the command. This prevents rapid, multiple executions from quick saves.<br><br><b>-e <i>&lt;regexp&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Provide a <i>regular expression</i> to exclude files or directories from being watched. Files matching this pattern will be ignored even if they are in a watched directory.<br><br><b>-g <i>&lt;glob&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specify a <i>glob pattern</i> to match files to watch. Use as an alternative to the <code>-r</code> (regular expression) option for simpler pattern matching.<br><br><b>-i</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Ignore common version control directories (e.g., <code>.git</code>, <code>.hg</code>, <code>.svn</code>, <code>.bzr</code>) and dependency directories (e.g., <code>node_modules</code>, <code>vendor</code>) from being watched.<br><br><b>-L <i>&lt;level&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Set the <i>log level</i> for <b>reflex</b> itself (e.g., <code>debug</code>, <code>info</code>, <code>warn</code>, <code>error</code>). This controls the verbosity of <b>reflex</b>'s internal output.<br><br><b>-m <i>&lt;num&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Set the <i>maximum number of events</i> to debounce before forcing command execution. This ensures the command eventually runs even if changes are continuous.<br><br><b>-r <i>&lt;regexp&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Provide a <i>regular expression</i> to match files to watch. Only files matching this pattern will trigger command execution. By default, it watches all files (`.*`).<br><br><b>-s</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Start the command immediately upon <b>reflex</b> startup, before any file changes occur. Useful for ensuring the service is running from the start.<br><br><b>-t <i>&lt;regexp&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Provide a <i>regular expression</i> that, if matched by a changed file, will trigger command execution. By default, any change (`.*`) triggers a run.<br><br><b>-x</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Do not clear the terminal screen before executing the command. This option overrides the <code>-c</code> option if both are specified.<br><br><b>-h, --help</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Display the help message, showing all available options and their usage, and then exit.<br><br><b>-v, --version</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Display the version information of <b>reflex</b> and then exit.<br><br>


title: DESCRIPTION
content:
<b>reflex</b> is a powerful and flexible command-line utility designed to watch files and directories for changes, automatically re-executing a specified command upon detecting modifications. It's particularly useful for developers, enabling real-time feedback during development cycles by recompiling code, restarting servers, or running tests whenever source files are updated.<br><br><b>reflex</b> supports various filtering options, allowing users to define specific files or patterns to watch (or ignore) using regular expressions or glob patterns. It can also debounce multiple rapid changes into a single execution and clear the terminal output for a cleaner development experience. Written in Go, it's cross-platform and efficient for diverse development environments.


title: CAVEATS
content:
<b>reflex</b> is primarily designed for development workflows and may not be suitable for high-performance, production monitoring systems where very low latency or guaranteed event delivery is critical. Performance might be affected when watching a very large number of files or directories, especially on older file systems or network mounts. The accuracy of file change detection can sometimes be limited by the underlying operating system's file system notification capabilities.


title: COMMON USE CASES
content:
<b>reflex</b> is widely used for auto-reloading web servers during front-end development, recompiling Go or other compiled languages on save, automatically running unit tests, or triggering build scripts for static site generators. Its flexibility allows it to integrate into various development pipelines, reducing manual intervention and speeding up the feedback loop.


title: PATTERN MATCHING
content:
Users should be aware of the differences between regular expressions (used with <code>-r</code> and <code>-e</code>) and glob patterns (used with <code>-g</code>). Regular expressions offer more power and precision for complex matching, while glob patterns are often simpler and more intuitive for basic file matching like <code>*.js</code> or <code>**/*.go</code>. Choosing the right pattern type is crucial for effective file watching.


title: HISTORY
content:
<b>reflex</b> is a relatively modern tool, implemented in Go. It was created to provide a simple, cross-platform, and efficient solution for the common development need of automatically re-running commands on file changes. Its design draws inspiration from similar tools in various language ecosystems (like `nodemon` for Node.js or `rackup` for Ruby) but offers a generic approach, making it applicable to any programming language or build system. Its active development reflects its utility in contemporary development workflows, emphasizing speed and ease of use.


title: SYNOPSIS
content:
<i>register_new_matrix_user</i> <i>[options]</i><br>or<br><i>register_new_matrix_user</i> <i>-c <B>CONFIG_FILE</B> -u <B>USERNAME</B> [-p <B>PASSWORD</B>] [--no-password] [--make-guest] [-a]</i>


title: PARAMETERS
content:
<b><i>-c <B>CONFIG_FILE</B></i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the path to the Synapse homeserver configuration file (e.g., <i>homeserver.yaml</i>). This is crucial for the script to connect to the correct database and settings.<br><br><b><i>-u <B>USERNAME</B></i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;The desired username for the new Matrix user. If omitted, the script may prompt for interactive input.<br><br><b><i>-p <B>PASSWORD</B></i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;The password for the new user. If omitted and <i>--no-password</i> is not used, the script will prompt for a password interactively.<br><br><b><i>--no-password</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Creates the user without an initial password. The user will need to use a password reset mechanism or be assigned one later.<br><br><b><i>--make-guest</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Registers the new user as a guest account. Guest accounts have limited permissions.<br><br><b><i>-a</i>, <i>--admin</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Grants administrator privileges to the newly created user. Admin users can manage other users, rooms, and homeserver settings.<br><br>


title: DESCRIPTION
content:
<i>register_new_matrix_user</i> is a Python script included with the Matrix Synapse homeserver software. It provides a command-line interface for administrators to directly create new user accounts on their Synapse instance. This utility is particularly useful for bulk user creation, setting up administrative accounts, or bypassing the standard user registration process, which might be disabled or require email verification. It allows specifying a username, password, and whether the user should be an administrator. The script requires access to the Synapse configuration file to function correctly and typically needs to be run with appropriate permissions from the Synapse virtual environment. It interacts directly with the homeserver's database to provision new user entries.


title: CAVEATS
content:
This command directly modifies the Synapse homeserver's database. Incorrect usage or running it against a live server without proper understanding could lead to data corruption or unexpected behavior. It should typically be run by the user account that owns the Synapse installation or with elevated privileges. Ensure the Synapse server is stopped or in a maintenance state if significant user management is being performed, though this specific script is usually safe to run while Synapse is running.


title: INTERACTIVE MODE
content:
If the <i>-u</i> or <i>-p</i> parameters are omitted, the script will typically run in an interactive mode, prompting the user to enter the username, password, and other details directly in the terminal.


title: LOCATION
content:
The exact path to the script can vary depending on the Synapse installation method (e.g., source, Debian package, Docker). Common locations include virtual environments (e.g., <i>/opt/matrix-synapse/env/bin/register_new_matrix_user</i>), Python site-packages, or within Docker containers.


title: PERMISSIONS
content:
The script needs read access to the Synapse configuration file and write access to the Synapse database. This usually means running it as the user that owns the Synapse process or with root privileges.


title: HISTORY
content:
The <i>register_new_matrix_user</i> script has been a fundamental part of the Matrix Synapse homeserver administration toolkit since its early development. It was introduced to provide a direct, programmatic way for server administrators to manage user accounts, complementing the standard registration flows which might involve email verification or be disabled on private instances. Its functionality has remained largely consistent, primarily focused on the core task of user provisioning, adapting slightly with Synapse database schema changes over time.


title: SYNOPSIS
content:
<b>rename</b> [<i>options</i>] '<i>s/search_pattern/replace_pattern/[flags]</i>' [<i>file...</i>]<br><i>Example:</i> <b>rename</b> 's/\.txt$/\.bak/' *.txt


title: PARAMETERS
content:
<b><b>-v</b>, <b>--verbose</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays the old and new names of each file being renamed, providing feedback on the operation.<br><br><b><b>-n</b>, <b>--no-act</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Performs a 'dry run'. It shows what files <i>would</i> be renamed without actually changing anything, crucial for testing complex regular expressions.<br><br><b><b>-f</b>, <b>--force</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Overwrites existing destination files without prompting.<br><br><b><b>-i</b>, <b>--interactive</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Prompts before overwriting an existing destination file, allowing the user to confirm or skip.<br><br><b><b>-o</b>, <b>--no-overwrite</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Do not overwrite existing files; if a target name already exists, the file is not renamed.<br><br><b><b>-k</b>, <b>--keep-structure</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Retain the directory structure when renaming files within subdirectories (often used with <i>find</i>).<br><br><b><b>-d</b>, <b>--directories</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Include directory names in the renaming operation, not just files.<br><br><b><b>-e</b>, <b>--expr</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Allows specifying the Perl expression on the command line, useful for scripting.<br><br><b><b>--version</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays the version information of the <i>rename</i> utility.<br><br><b><b>--help</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Shows a concise help message with available options.<br><br>


title: DESCRIPTION
content:
<i>rename</i> is a powerful command-line utility in Linux used for batch renaming of files based on specified rules. Unlike the simpler <i>mv</i> command which renames one file at a time or moves it, <i>rename</i> can apply a transformation to multiple filenames concurrently. The most widely used version, often referred to as Perl <i>rename</i> (or sometimes <i>prename</i>), leverages Perl's regular expression capabilities to provide flexible and sophisticated renaming operations. This allows users to perform complex patterns of substitution, deletion, or insertion within filenames. For instance, one can easily change file extensions, add prefixes/suffixes, remove specific characters, or reformat names across hundreds or thousands of files in a single command. It's an indispensable tool for system administrators and users managing large collections of files.


title: CAVEATS
content:
<ul><li><b>Version Ambiguity</b>: There are two distinct versions of the <i>rename</i> command on Linux: the Perl-based <i>rename</i> (analyzed here) and a simpler <i>util-linux</i> version (e.g., <i>rename oldname newname file...</i>). Their syntax and capabilities are vastly different. Always verify which version is installed on your system (e.g., <i>man rename</i> or <i>rename --version</i>).</li><li><b>Irreversible Operations</b>: Renaming files is a destructive operation with no built-in 'undo'. Always use the <b>--no-act</b> or <b>-n</b> option first to test your renaming logic, especially with complex regular expressions.</li><li><b>Regular Expression Complexity</b>: Incorrectly formulated regular expressions can lead to unintended or partial renames, or affect more files than intended.</li><li><b>Permissions</b>: Ensure you have write permissions in the directories where files are being renamed.</li><li><b>Special Characters</b>: Be cautious when dealing with filenames containing special characters (spaces, hyphens, etc.) as they may require proper escaping or quoting in shell commands.</li></ul>


title: REGULAR EXPRESSION SYNTAX (PERL)
content:
The core of Perl <i>rename</i>'s power lies in its use of Perl regular expressions, typically in the format <code>'s/<i>search_pattern</i>/<i>replace_pattern</i>/[<i>flags</i>]'</code>.<br><ul><li><i>search_pattern</i>: The regular expression to find within the filenames.</li><li><i>replace_pattern</i>: The string that will replace the matched <i>search_pattern</i>. Backreferences (e.g., <code>$1</code>, <code>$2</code>) from captured groups in the <i>search_pattern</i> can be used here.</li><li><i>flags</i>: Optional modifiers like <b>g</b> (global replacement, replace all occurrences), <b>i</b> (case-insensitive), <b>s</b> (single line mode), <b>x</b> (extended regex format, ignore whitespace for readability).</li></ul>


title: COMMON USAGE PATTERNS
content:
<ul><li>Changing file extensions: <code>rename 's/\.jpeg$/\.jpg/' *.jpeg</code></li><li>Adding prefixes/suffixes: <code>rename 's/^/new_/' *</code> (prefix); <code>rename 's/$/_old/' *</code> (suffix)</li><li>Removing parts of filenames: <code>rename 's/ - Copy//' *</code></li><li>Converting spaces to underscores: <code>rename 's/ /_/g' *</code></li></ul>


title: HISTORY
content:
The <i>rename</i> command has a bifurcated history on Linux systems. The widely popular and powerful version, which is the focus of this analysis, is a Perl script that leverages Perl's strong regular expression engine. This version is often found pre-installed or easily installable on most distributions (e.g., Debian/Ubuntu's <i>perl-rename</i> package). Its development stemmed from the need for a more flexible batch renaming tool than <i>mv</i> could provide, especially for operations requiring pattern matching and substitution. Concurrently, a simpler <i>rename</i> utility is part of the <i>util-linux</i> project, commonly found on Red Hat-based systems (like Fedora, CentOS). This version is limited to a simple <i>oldname newname</i> transformation for a single file or a global <i>string replace</i> for multiple files, lacking the full power of regex. Due to its superior flexibility and regex capabilities, the Perl version has become the de-facto <i>rename</i> for advanced batch operations, making it an essential tool for scripting and file management.


title: SYNOPSIS
content:
<B>reuse</B> <I>[options]</I> <B>lint</B> <I>[paths...]</I><br><B>reuse</B> <I>[options]</I> <B>addheader</B> <I>[<B>-l</B> <I>ID</I> | <B>-c</B> <I>TEXT</I> | <B>-H</B> <I>TEXT</I> | <B>-y</B> <I>YEARS</I> | <B>--single-line</B> | <B>--template</B> | <B>--merge-copyrights</B>] files...</I><br><B>reuse</B> <I>[options]</I> <B>addlicense</B> <I>license_id [output_dir]</I><br><B>reuse</B> <I>[options]</I> <B>download</B><br><B>reuse</B> <I>[options]</I> <B>init</B><br><B>reuse</B> <I>[options]</I> <B>spdx</B> <I>[paths...]</I><br><B>reuse</B> <B>help</B> <I>[command]</I><br><B>reuse</B> <B>version</B>


title: PARAMETERS
content:
<b>--help, -h</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Display help information for the command or a specific subcommand.<br><br><b>--version</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Show the version number of the reuse tool.<br><br><b>--verbose, -v</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Increase the verbosity of the output.<br><br><b>--quiet, -q</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Suppress all output except for errors.<br><br><b><B>lint</B></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Checks project files for REUSE specification compliance, identifying missing headers or license texts.<br><br><b><B>addheader</B> <I>files...</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Adds copyright and license headers to specified files, automatically detecting comment styles.<br><br><b><B>addlicense</B> <I>license_id</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Downloads and adds a full license text file (e.g., <I>GPL-3.0-or-later</I>) to the project's <I>LICENSES/</I> directory.<br><br><b><B>download</B></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Downloads all missing license texts required by the project based on detected SPDX license identifiers.<br><br><b><B>init</B></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Initializes a new project for REUSE compliance, creating necessary directories and configuration files.<br><br><b><B>spdx</B></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Generates a SPDX Bill of Materials (<B>BOM</B>) for the project, summarizing licensing information in a standard format.<br><br><b>--license <ID>, -l <ID></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specify the SPDX license identifier (e.g., <I>GPL-3.0-or-later</I>) for the header. (Used with <B>addheader</B>)<br><br><b>--copyright <TEXT>, -c <TEXT></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Add a custom copyright statement to the header. (Used with <B>addheader</B>)<br><br><b>--holder <TEXT>, -H <TEXT></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specify the copyright holder for the header. (Used with <B>addheader</B>)<br><br><b>--year <YEARS>, -y <YEARS></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specify the copyright years (e.g., <I>2023</I> or <I>2020-2023</I>) for the header. (Used with <B>addheader</B>)<br><br><b>--single-line</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Add a compact, single-line copyright and license header where possible. (Used with <B>addheader</B>)<br><br><b>--merge-copyrights</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Merge existing copyright lines when adding headers to avoid duplicates. (Used with <B>addheader</B>)<br><br>


title: DESCRIPTION
content:
The `reuse` command-line tool implements the <I>REUSE Specification</I>, a set of best practices for declaring software licenses and copyrights within a project. Developed by the Free Software Foundation Europe (<B>FSFE</B>), the REUSE Specification aims to make it easy for humans and machines to understand how a project is licensed by standardizing the placement and content of licensing information.<br><br>The `reuse` tool helps developers comply with this specification by providing functionalities to lint a project for compliance issues, automatically add copyright and license headers to files, integrate full license texts, and manage licensing metadata. It simplifies the process of ensuring that every file in a project explicitly states its copyright holder and license, thereby improving legal clarity and promoting open-source principles. The tool is particularly useful for projects that integrate various components with different licenses, helping to prevent licensing ambiguities and facilitate proper attribution.


title: CAVEATS
content:
The `reuse` command is not a standard pre-installed Linux utility; it typically needs to be installed separately, commonly via Python's package manager (<I>pip</I>). Its primary use case is within software development projects to manage licensing information, rather than general system administration or file manipulation. Users should have a basic understanding of the REUSE Specification to effectively utilize the tool. As it modifies files (e.g., adding headers), it is highly recommended to use it within a version-controlled environment (e.g., <I>Git</I>) to prevent unintended data loss or irreversible changes.


title: REUSE SPECIFICATION
content:
The `reuse` tool strictly adheres to the <I>REUSE Specification</I> (version 3.0), which dictates how licensing and copyright information should be stored within a project. This includes requirements for a <I>LICENSES/</I> directory for full license texts, license identifiers in file headers, and optional <I>.reuse/dep5</I> files for package-level metadata.


title: INTEGRATION WITH WORKFLOWS
content:
Due to its command-line nature, `reuse` can be easily integrated into continuous integration/continuous deployment (<B>CI/CD</B>) pipelines. This allows for automated checks of REUSE compliance with every commit or build, ensuring that license information remains consistent and correct throughout the project's lifecycle.


title: SUPPORTED FILE TYPES
content:
The tool supports a wide variety of programming languages and file types, automatically detecting the appropriate comment style for adding headers based on file extensions or shebang lines. This broad compatibility ensures that licensing information can be uniformly applied across diverse codebases.


title: HISTORY
content:
The `reuse` tool is an implementation of the REUSE Specification, which was developed by the Free Software Foundation Europe (<B>FSFE</B>). The specification was first publicly launched around 2017-2018 with the goal of providing a clear, standardized, and machine-readable way to declare licensing and copyright information within software projects. The tool itself was developed concurrently to help projects automatically comply with these guidelines, addressing the growing complexity of licensing in modern software development where components from various sources with differing licenses are often integrated. Its development was driven by the need to simplify auditing, enhance legal clarity, and promote proper attribution in open-source software.


title: SYNOPSIS
content:
<b>rexec</b> [<b>-l</b> <i>username</i>] [<b>-p</b> <i>password</i>] [<b>-d</b>] [<b>-n</b>] <i>host</i> <i>command</i> [<i>arguments...</i>]


title: PARAMETERS
content:
<b><i>host</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;The remote host on which the command will be executed.<br><br><b><i>command</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;The command to be executed on the remote host.<br><br><b><i>arguments...</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Optional arguments to be passed to the <i>command</i>.<br><br><b><b>-l</b> <i>username</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the username to be used for authentication on the remote host. If not provided, the local username is typically used, or <i>rexec</i> might prompt for one.<br><br><b><b>-p</b> <i>password</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Provides the password for authentication on the remote host. <b>Use with extreme caution</b> as this transmits the password in plain text over the network. If not provided, <i>rexec</i> will usually prompt for the password.<br><br><b><b>-d</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Enables debugging output, providing more verbose information about the connection and execution process.<br><br><b><b>-n</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Redirects the standard input of the remote command to <i>/dev/null</i>, meaning the remote command will not receive any input from the local standard input.<br><br>


title: DESCRIPTION
content:
<i>rexec</i> is a client program designed to execute commands on a remote host. It connects to the <i>rexecd</i> daemon running on the target machine, authenticates the user, and then runs the specified command. Unlike <i>rsh</i>, <i>rexec</i> traditionally prompts for a password if one is required and not provided, offering a slight difference in its authentication flow. <br><br>However, a critical aspect of <i>rexec</i> is its inherent insecurity: all data, including usernames, passwords, and the command output, is transmitted in plain text over the network. This makes it highly vulnerable to eavesdropping and interception. Due to these significant security limitations, <i>rexec</i> has been largely superseded by more secure alternatives like <i>ssh</i> (Secure Shell), which encrypts all communications. Its use is strongly discouraged for modern networked environments and is primarily found in legacy systems or specific, controlled environments where security is not a primary concern or a secure alternative is not feasible.


title: CAVEATS
content:
<b>Security Risk:</b> <i>rexec</i> transmits all credentials (usernames and passwords) and command output in plain text, making it highly vulnerable to network sniffing and unauthorized access. Its use is strongly discouraged for secure environments.<br><b>Requires Daemon:</b> The remote host must be running the <i>rexecd</i> daemon for <i>rexec</i> to function.<br><b>Firewall Considerations:</b> <i>rexec</i> typically uses TCP port 512, which must be open on firewalls between the client and server.


title: AUTHENTICATION PROCESS
content:
<i>rexec</i> handles authentication by sending the username and password to the remote <i>rexecd</i> daemon. If the <b>-p</b> option is not used or if the password is not provided via an environment variable (like <i>REXEC_PASS</i> on some systems), <i>rexec</i> will interactively prompt the user for the password before attempting to execute the command.


title: STANDARD PORT
content:
<i>rexec</i> primarily communicates over TCP port 512. This port must be accessible on the remote host and any intermediary firewalls for the command to succeed.


title: HISTORY
content:
<i>rexec</i> is one of the original 'r-commands' (along with <i>rsh</i> and <i>rlogin</i>) developed as part of the Berkeley Software Distribution (BSD) Unix in the early days of networked computing. It gained prominence in the 1980s as a simple way to execute commands remotely. However, its unencrypted nature became a significant security liability as network usage grew and security threats evolved. The advent of <i>ssh</i> (Secure Shell) in the mid-1990s, which offered robust encryption and secure authentication, led to the rapid decline in <i>rexec</i>'s usage and its deprecation in favor of more secure alternatives.


title: SYNOPSIS
content:
<b>rkdeveloptool</b> [<i>options</i>] <i>command</i> [<i>arguments</i>]<br><br>Common usage examples:<br><b>rkdeveloptool</b> <i>listdevice</i><br><b>rkdeveloptool</b> <i>db</i> <i>&lt;loader_file&gt;</i><br><b>rkdeveloptool</b> <i>writeflash</i> <i>&lt;partition_name&gt; &lt;image_file&gt;</i><br><b>rkdeveloptool</b> <i>upgrade</i> <i>&lt;firmware_image.img&gt;</i>


title: PARAMETERS
content:
<b>listdevice</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Lists all connected Rockchip devices detected in Maskrom or Loader mode.<br><br><b>db <i>&lt;loader_file&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Downloads the specified boot loader file to the device's RAM. This is often the first step before further operations.<br><br><b>readflash <i>&lt;partition&gt; &lt;output_file&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Reads data from a specified flash partition on the device and saves it to a local file.<br><br><b>writeflash <i>&lt;partition&gt; &lt;image_file&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Writes the content of the specified image file to a designated flash partition on the device.<br><br><b>eraseflash <i>&lt;partition&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Erases a specific flash partition on the connected device.<br><br><b>reset</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Resets the connected Rockchip device, typically used after flashing operations to reboot.<br><br><b>boot</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Tells the device to boot from its internal storage after a loader has been downloaded.<br><br><b>upgrade <i>&lt;firmware_image.img&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Performs a complete firmware upgrade using a single unified firmware image file (.img).<br><br><b>readid</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Reads the unique chip ID from the connected device.<br><br><b>test <i>&lt;argument&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Executes internal test functions (less commonly used by end-users).<br><br>


title: DESCRIPTION
content:
rkdeveloptool is a command-line utility designed for interacting with Rockchip-based devices, primarily for firmware development and flashing operations.<br><br>It allows users to download boot loaders, flash firmware images (such as ROMs, bootloaders, kernel, and root file systems) to the device's internal storage (e.g., eMMC, NAND, SPI flash), read flash content, erase partitions, and reset the device.<br><br>The tool typically communicates with the Rockchip device when it is in a special mode, often referred to as 'Maskrom' mode or 'Loader' mode, which is accessible via a USB connection. It's an indispensable tool for developers working on Rockchip platforms, custom ROMs, or recovering bricked devices.


title: CAVEATS
content:
<b>rkdeveloptool</b> requires specific USB drivers to be installed and correctly configured on the host system (e.g., <i>libusb</i> and <i>udev</i> rules on Linux, Rockchip drivers on Windows).<br>The device must be in the correct mode (Maskrom or Loader) for the tool to detect and interact with it, often requiring specific button presses (e.g., recovery button) during power-up.<br>Incorrect usage, flashing corrupted images, or interrupting the process can lead to device bricking.<br>Compatibility can vary between different Rockchip SoC models; sometimes specific versions of the tool are required for certain chips or firmware.


title: TYPICAL FLASHING WORKFLOW
content:
A common workflow involves:<br>1. Putting the device into Maskrom mode.<br>2. Running <b>rkdeveloptool</b> <i>listdevice</i> to confirm detection.<br>3. Downloading the boot loader: <b>rkdeveloptool</b> <i>db</i> <i>&lt;loader.bin&gt;</i>.<br>4. Flashing individual partitions: <b>rkdeveloptool</b> <i>writeflash</i> <i>&lt;partition&gt; &lt;image&gt;</i> for boot, kernel, rootfs, etc.<br>5. Resetting the device: <b>rkdeveloptool</b> <i>reset</i>.<br>Alternatively, for a full image: <b>rkdeveloptool</b> <i>upgrade</i> <i>&lt;firmware.img&gt;</i> after step 3.


title: MASKROM VS. LOADER MODE
content:
<b>Maskrom mode</b> is a low-level, unchangeable boot mode built into the SoC's ROM, used for initial device detection and downloading a secondary bootloader. <b>Loader mode</b> (or 'Bootloader mode') is entered after a loader is successfully downloaded to RAM, allowing more complex operations like partition flashing and full firmware upgrades. The tool often transitions between these modes automatically or explicitly via commands like <i>db</i>.


title: HISTORY
content:
<b>rkdeveloptool</b> is developed and maintained by Rockchip, a leading Chinese fabless semiconductor company specializing in SoCs for various devices. The tool has evolved alongside their chip product lines (e.g., RK3288, RK3399, RV1109/RV1126, RK3588), adapting to new hardware features and flashing protocols. It's a fundamental part of the Rockchip SDKs provided to developers and manufacturers, primarily facilitating low-level flashing and debugging of Rockchip silicon from a host PC.


title: SYNOPSIS
content:
<b>rkhunter</b> [<i>options</i>]<br>Example: <b>rkhunter --check</b><br>Example: <b>rkhunter --update</b>


title: PARAMETERS
content:
<b>--check</b><br>&nbsp;&nbsp;&nbsp;&nbsp;<i>Executes a full system scan for rootkits, backdoors, and other anomalies. This is the primary usage mode.</i><br><br><b>--update</b><br>&nbsp;&nbsp;&nbsp;&nbsp;<i>Updates the data files used by <b>rkhunter</b> (e.g., rootkit definitions, backdoor signatures, file properties). Requires internet connectivity.</i><br><br><b>--propupdate</b><br>&nbsp;&nbsp;&nbsp;&nbsp;<i>Updates the file properties database for files that have changed legitimately (e.g., after system updates or software installations) to prevent false positives.</i><br><br><b>--versioncheck</b><br>&nbsp;&nbsp;&nbsp;&nbsp;<i>Checks the <b>rkhunter</b> website for a new version of the program.</i><br><br><b>--list [test]</b><br>&nbsp;&nbsp;&nbsp;&nbsp;<i>Lists the available tests categories or, if a test category is specified, lists the files associated with that test.</i><br><br><b>--quiet</b><br>&nbsp;&nbsp;&nbsp;&nbsp;<i>Suppresses informational messages, only displaying warnings and errors during the scan.</i><br><br><b>--report-warnings-only</b><br>&nbsp;&nbsp;&nbsp;&nbsp;<i>Similar to --quiet, but explicitly only reports warnings, excluding informational messages.</i><br><br><b>--disable [test,...]</b><br>&nbsp;&nbsp;&nbsp;&nbsp;<i>Disables one or more specific tests from being performed during a scan. Tests are comma-separated.</i><br><br><b>--enable [test,...]</b><br>&nbsp;&nbsp;&nbsp;&nbsp;<i>Enables one or more specific tests, overriding any default disabling in the configuration.</i><br><br><b>--skip-keypress</b><br>&nbsp;&nbsp;&nbsp;&nbsp;<i>Prevents <b>rkhunter</b> from pausing and requiring a keypress during checks. Useful for scripting.</i><br><br><b>--clean</b><br>&nbsp;&nbsp;&nbsp;&nbsp;<i>Deletes all temporary files created by <b>rkhunter</b> during its operation.</i><br><br><b>--configure</b><br>&nbsp;&nbsp;&nbsp;&nbsp;<i>Launches the configuration file generator, allowing interactive setup of <b>rkhunter</b>.</i><br><br><b>--display-config</b><br>&nbsp;&nbsp;&nbsp;&nbsp;<i>Displays the current configuration settings that <b>rkhunter</b> is using.</i><br><br><b>--version</b><br>&nbsp;&nbsp;&nbsp;&nbsp;<i>Shows the installed version number of <b>rkhunter</b>.</i><br><br><b>--help</b><br>&nbsp;&nbsp;&nbsp;&nbsp;<i>Displays the help message with a list of available options.</i><br><br>


title: DESCRIPTION
content:
<b>rkhunter</b> (Rootkit Hunter) is a free and open-source command-line tool for Linux and UNIX-like systems. It performs comprehensive scans to detect various types of malicious software, including rootkits, backdoors, sniffers, and local exploits.<br><br>The tool operates by comparing various system characteristics against a database of known rootkit signatures, hashes, and patterns. These checks include:<br><i>- Comparing SHA-1 hashes of critical system binaries against a known good database.</i><br><i>- Looking for hidden files and directories.</i><br><i>- Checking for incorrect file permissions on executables.</i><br><i>- Scanning for suspicious strings in kernel modules.</i><br><i>- Checking for common rootkit files and directories.</i><br><i>- Analyzing network ports and system processes for suspicious activity.</i><br><br><b>rkhunter</b> is an essential component of a layered security strategy, helping system administrators identify compromises that might otherwise go unnoticed. Regular execution and database updates are crucial for its effectiveness.


title: CAVEATS
content:
<i>- <b>Not Real-time Prevention:</b> <b>rkhunter</b> is a detection tool, not a prevention tool. It detects compromises after they have occurred, not prevents them.</i><br><i>- <b>False Positives:</b> It can sometimes report legitimate system changes as warnings, especially after system updates. Regular use of <b>--propupdate</b> mitigates this.</i><br><i>- <b>Database Dependency:</b> Its effectiveness heavily relies on regularly updated databases. Outdated databases may fail to detect new threats.</i><br><i>- <b>Rootkit Hiding:</b> A sophisticated rootkit on an already compromised system might hide itself from detection by tools like <b>rkhunter</b>. For critical investigations, running from a trusted live environment is recommended.</i><br><i>- <b>Baseline Needed:</b> For optimal results, <b>rkhunter</b> should ideally be run on a freshly installed, clean system to establish a trustworthy baseline.</i>


title: INSTALLATION
content:
<b>rkhunter</b> is widely available in the official package repositories of most Linux distributions. You can typically install it using your distribution's package manager, for example:<br><i>- Debian/Ubuntu:</i> <b>sudo apt install rkhunter</b><br><i>- Red Hat/CentOS/Fedora:</i> <b>sudo yum install rkhunter</b> or <b>sudo dnf install rkhunter</b><br>After installation, it's highly recommended to run <b>sudo rkhunter --update</b> to download the latest threat definitions.


title: USAGE BEST PRACTICES
content:
<i>- <b>Regular Updates:</b> Always run <b>sudo rkhunter --update</b> frequently (e.g., daily) to ensure you have the latest rootkit definitions.</i><br><i>- <b>Scheduled Scans:</b> Automate scans via cron jobs (e.g., daily or weekly) using <b>sudo rkhunter --check --skip-keypress</b>.</i><br><i>- <b>Property Updates:</b> After kernel updates, system upgrades, or significant software installations, run <b>sudo rkhunter --propupdate</b> to update the file properties database and avoid numerous false positives.</i><br><i>- <b>Review Logs:</b> Always review the scan results and log files (usually in <b>/var/log/rkhunter.log</b>) for any warnings or suspicious findings.</i>


title: HISTORY
content:
<b>rkhunter</b> was initially developed by Michael Boelen and released in 2003. It quickly gained popularity within the Linux and UNIX security communities as a vital tool for identifying system compromises. As an open-source project, it has benefited from community contributions and ongoing maintenance, allowing it to adapt to new rootkit techniques and maintain its relevance in the ever-evolving threat landscape. Its design focuses on simplicity and effectiveness, making it accessible to both experienced administrators and security enthusiasts.


title: PARAMETERS
content:
<b><b>-p</b>, <b>--parents</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Remove <i>DIRECTORY</i> and its <i>ancestor</i> directories if they become empty after the removal. For example, <code>rmdir -p a/b/c</code> will remove <code>c</code>, then <code>b</code> if <code>b</code> is empty, then <code>a</code> if <code>a</code> is empty.<br><br><b><b>-v</b>, <b>--verbose</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Output a diagnostic message for every directory processed, indicating success or failure.<br><br><b><b>--ignore-fail-on-non-empty</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Suppress error messages when attempting to remove a directory that is not empty. The command will still fail to remove the non-empty directory but won't output an error to standard error.<br><br><b><b>--help</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Display a help message and exit.<br><br><b><b>--version</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Output version information and exit.<br><br>


title: DESCRIPTION
content:
The <b>rmdir</b> command is a standard Unix and Linux utility used to remove <i>empty</i> directories from the file system. Unlike <b>rm -r</b>, <b>rmdir</b> will only succeed if the specified directory contains no files or subdirectories. This makes it a safer option for cleaning up directory structures, preventing accidental deletion of important data. It's commonly used for tidying up empty branches of a directory tree, either manually or within shell scripts. When a directory is successfully removed, <b>rmdir</b> provides no output unless the <b>--verbose</b> option is used.


title: CAVEATS
content:
<ul><li><b>rmdir</b> can <i>only</i> remove directories that are completely empty. If a directory contains any files or subdirectories (even hidden ones), <b>rmdir</b> will fail with an error.</li><li>To remove non-empty directories, the <b>rm -r</b> command must be used, which is significantly more powerful and potentially dangerous, requiring extreme caution.</li><li>You must have appropriate permissions: write permission in the <i>parent</i> directory of the directory you wish to remove, and execute permission for the directory itself.</li></ul>


title: RECURSIVE EMPTY DIRECTORY REMOVAL
content:
While <b>rmdir</b> itself does not have a recursive option to traverse and empty non-empty directories, its <b>--parents</b> option allows it to remove an entire path of empty directories. For more complex recursive cleanups of <i>truly empty</i> directories, <b>rmdir</b> is often combined with <b>find</b>. For example, <code>find . -type d -empty -delete</code> is a common and efficient way to remove all empty subdirectories within a given path. Alternatively, <code>find . -type d -empty -exec rmdir {} +</code> can be used, although <b>-delete</b> is often preferred for simplicity and efficiency where available.


title: EXIT STATUS
content:
<b>rmdir</b> returns an exit status of 0 upon successful completion. A non-zero exit status indicates an error, such as trying to remove a non-empty directory, a directory that does not exist, or a permissions issue. This behavior is crucial for scripting, allowing conditional execution based on the command's outcome.


title: HISTORY
content:
<b>rmdir</b> is a foundational command in Unix-like operating systems, part of the core utilities since the early versions of Unix. It was designed to provide a specific, safe mechanism for directory removal, distinct from the more general-purpose <b>rm</b> command. Its core functionality has remained remarkably consistent, reinforcing its role as a simple yet essential tool for managing the file system hierarchy.


title: DESCRIPTION
content:
The command <i>rpl8</i> is not a standard or commonly recognized utility within most Linux distributions. Searches of official man pages, package repositories (like Debian/Ubuntu's APT or Red Hat/Fedora's DNF/YUM), and common Linux command documentation yield no specific command named <i>rpl8</i>.<br><br>It is highly probable that <i>rpl8</i> is either a typographical error for the widely used string replacement command <b>rpl</b>, a very specific internal script or alias unique to a particular environment, or an very obscure/obsolete utility. If the intention was to find a tool for batch string replacement in files, <b>rpl</b> or <b>sed</b> are the standard and powerful utilities available on virtually all Linux systems.


title: CAVEATS
content:
As <i>rpl8</i> is not a standard command, its behavior, if it exists as a custom script or alias, would be entirely dependent on its specific implementation. Users seeking a general-purpose string replacement tool should use <b>rpl</b> or <b>sed</b>.


title: COMMON STRING REPLACEMENT TOOLS
content:
For tasks involving string replacement in files, common Linux utilities include:<br><b>rpl</b>: A dedicated, user-friendly tool for replacing strings in files, often considered simpler for basic tasks than sed.<br><b>sed</b>: The stream editor, a powerful and versatile tool for text transformations, capable of complex pattern matching and substitution.<br><b>awk</b>: A powerful text processing language, suitable for more complex data manipulation and reporting.<br><b>perl</b>: A highly capable scripting language often used for text processing due to its strong regular expression support.


title: HISTORY
content:
N/A: No historical records for a standard <i>rpl8</i> command exist. The <b>rpl</b> command, however, has been developed as a more user-friendly alternative to <b>sed</b> for simpler string replacements across multiple files.


title: SYNOPSIS
content:
<i>Rscript</i> [<i>options</i>] <i>file</i> [<i>args</i>]<br><i>Rscript</i> [<i>options</i>] <b>-e</b> <i>expression</i> [<i>args</i>]


title: PARAMETERS
content:
<b><b>-e</b> <i>expression</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Executes the R code provided directly as <i>expression</i>. This is useful for running short R commands without creating a script file.<br><br><b><b>--vanilla</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Starts R without saving or restoring the workspace, history, or startup files (like .Rprofile). This is the default behavior for <i>rscript</i> and is recommended for clean, reproducible runs.<br><br><b><b>--save</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Explicitly saves the workspace image to .RData in the current working directory at the end of the script execution.<br><br><b><b>--no-save</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Prevents saving the workspace image. This is the default for <i>rscript</i>, ensuring a clean exit without modifying the environment.<br><br><b><b>--restore</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Explicitly restores a previously saved workspace image from .RData. This is not the default for <i>rscript</i>.<br><br><b><b>--no-restore</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Prevents restoring a previously saved workspace. This is the default for <i>rscript</i>.<br><br><b><b>--slave</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;A convenient shorthand for <b>--vanilla --no-restore --no-save --no-environ --no-site-file --no-Renviron --no-Rprofile --no-readline</b>. Ensures a very clean, quiet, and non-interactive start, ideal for background processes.<br><br><b><b>--verbose</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Prints detailed messages during the R startup process, which can be helpful for debugging environment issues.<br><br><b><b>--version</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Prints the R version information (including platform, R version, etc.) and then exits immediately.<br><br><b><b>--help</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays a help message with available options for <i>rscript</i> and then exits.<br><br><b><b>--args</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Signals that all subsequent arguments on the command line should be passed directly to the R script itself, rather than being interpreted as <i>rscript</i> options. These can be accessed via <i>commandArgs(trailingOnly=TRUE)</i> within R.<br><br><b><b>--default-packages=</b><i>list</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies a comma-separated <i>list</i> of packages to be loaded automatically at R startup, overriding the default set of packages.<br><br>


title: DESCRIPTION
content:
<i>rscript</i> is a command-line utility that allows for the execution of R scripts or R expressions directly from the shell, bypassing the need for an interactive R session. It is an essential tool for automating R-based tasks, batch processing data, and integrating R code into larger shell scripts or workflows. By default, <i>rscript</i> operates in a non-interactive mode, meaning it does not save or restore the workspace, ensuring clean and reproducible script executions. It can execute code from a specified R script file or directly from a string expression provided as an argument, making it highly flexible for various scripting needs. Its primary purpose is to enable R to be used seamlessly in automated environments.


title: CAVEATS
content:
By default, <i>rscript</i> operates in a clean, non-interactive mode, meaning it does not save or restore the workspace (similar to <b>--vanilla</b>). This is highly beneficial for reproducibility and automation but means any persistent data or objects must be explicitly handled within your R script (e.g., by reading/writing files). Since there's no interactive graphical display, any plots or visualizations must be saved to a file format (e.g., PDF, PNG) directly from within the R script. Robust error handling and logging should be managed either within the R script or by monitoring <i>rscript</i>'s exit code in the calling shell script.


title: ARGUMENT PASSING TO R SCRIPTS
content:
Arguments provided on the command line after the script filename (or <b>-e</b> expression) are accessible within the R script using the <i>commandArgs(trailingOnly=TRUE)</i> function. For example, if you run <i>rscript myscript.R arg1 arg2</i>, then <i>commandArgs(trailingOnly=TRUE)</i> within <i>myscript.R</i> would return a character vector <i>c("arg1", "arg2")</i>.


title: EXIT STATUS
content:
<i>rscript</i> typically exits with status 0 on successful execution. If the R script itself explicitly calls <i>quit(status=N)</i>, where <i>N</i> is a non-zero integer, <i>rscript</i> will propagate that exit status. This feature is crucial for robust error checking in shell scripts and automated workflows, allowing them to react appropriately to failures within the R script.


title: HISTORY
content:
<i>rscript</i> was introduced as a streamlined front-end for executing R code non-interactively, making it significantly easier to integrate R scripts into shell environments, cron jobs, and other automated systems. Prior to its existence, users often relied on invoking the main <i>R</i> executable with specific batch-mode arguments (e.g., <i>R CMD BATCH</i>). <i>rscript</i> simplifies and standardizes these common non-interactive use cases, providing a more intuitive interface for scripting.


title: PARAMETERS
content:
<b><b>-u</b> <i>URL</i>, <b>--url=</b><i>URL</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies an RSS/Atom feed URL to monitor. Can be used multiple times, or URLs can be provided as positional arguments.<br><br><b><b>-i</b> <i>SECONDS</i>, <b>--interval=</b><i>SECONDS</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets the polling interval in seconds. <b>rsstail</b> will check for new entries every <i>SECONDS</i> seconds. Default is often 300 (5 minutes).<br><br><b><b>-n</b>, <b>--new</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays only new entries found since the last check. This is often the default behavior.<br><br><b><b>-f</b>, <b>--follow</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Equivalent to <b>tail -f</b>. Continuously monitors the feed and outputs new entries as they arrive. Implies <b>-n</b>.<br><br><b><b>-a</b>, <b>--all</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays all entries found in the feed on the first fetch, then only new ones on subsequent checks. Overrides <b>-n</b>.<br><br><b><b>-l</b> <i>COUNT</i>, <b>--limit=</b><i>COUNT</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Limits the number of entries displayed on the first fetch (if <b>--all</b> is used) or per update.<br><br><b><b>-e</b> <i>ELEMENTS</i>, <b>--elements=</b><i>ELEMENTS</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies which elements of a feed entry to display. Common elements include <b>title</b>, <b>link</b>, <b>date</b>, <b>description</b>. Elements are usually comma-separated, e.g., <b>-e title,link</b>.<br><br><b><b>-q</b>, <b>--quiet</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Suppresses initial output, showing only entries that appear after <b>rsstail</b> starts monitoring.<br><br><b><b>-v</b>, <b>--verbose</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Increases verbosity, showing more information about the fetching process and feed parsing.<br><br><b><b>-h</b>, <b>--help</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays a help message and exits.<br><br><b><b>-d</b>, <b>--debug</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Enables debug output, useful for troubleshooting parsing issues.<br><br><b><b>-o</b> <i>FORMAT</i>, <b>--output=</b><i>FORMAT</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Defines a custom output format string using placeholders (e.g., <b>%title% - %link%</b>).<br><br><b><b>-k</b> <i>FILE</i>, <b>--keep=</b><i>FILE</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Stores processed entries in a specified <i>FILE</i> to avoid re-displaying them across <b>rsstail</b> invocations, enabling state persistence.<br><br>


title: DESCRIPTION
content:
<b>rsstail</b> is a command-line utility designed to monitor RSS and Atom feeds in a manner similar to the standard <b>tail -f</b> command for log files.<br><br>It periodically fetches content from specified feed URLs and displays new entries as they appear, making it an ideal tool for keeping up with news, blog posts, or any frequently updated content without needing a full-fledged feed reader.<br><br>Users can specify the polling interval, control which elements of the feed (like title, link, description) are displayed, and filter the output. Its simplicity and command-line nature make it particularly useful for scripting, integrating into custom dashboards, or for system administrators who prefer terminal-based tools for quick updates and monitoring.


title: CAVEATS
content:
<b>rsstail</b> is not a standard Linux command shipped with most distributions; it typically needs to be installed separately, often as a Perl script or from a specific package. Its functionality relies heavily on network connectivity to fetch feed content. While robust, it may encounter issues with malformed RSS/Atom feeds or unusual encoding.<br><br>Frequent polling with short intervals can consume network bandwidth and place a load on the feed server. As a command-line tool, it lacks the rich interactive features of graphical or more advanced terminal-based RSS readers.


title: <I>OUTPUT CUSTOMIZATION</I>
content:
<b>rsstail</b> offers flexible output customization through the <b>-e</b> (<b>--elements</b>) and <b>-o</b> (<b>--output</b>) options. Users can choose to display specific components of a feed entry, such as <b>title</b>, <b>link</b>, <b>date</b>, <b>description</b>, or even <b>author</b>.<br><br>The <b>--output</b> option allows for defining a custom format string, using placeholders like <b>%title%</b> or <b>%link%</b>, enabling users to tailor the display exactly to their needs, making it highly adaptable for scripting and integration with other command-line tools.


title: <I>STATE PERSISTENCE</I>
content:
To prevent re-displaying already seen entries across different <b>rsstail</b> invocations, the <b>-k</b> (<b>--keep</b>) option can be used. This option specifies a file where <b>rsstail</b> stores a record of the entries it has already processed. This allows the command to maintain state, ensuring that only truly new entries are shown even if <b>rsstail</b> is stopped and restarted. This feature is particularly useful in automated scripts or long-running sessions where continuous, unique updates are desired.


title: HISTORY
content:
<b>rsstail</b> emerged in the early 2000s, coinciding with the growing popularity of RSS (Really Simple Syndication) as a web feed format. It was typically implemented as a Perl script, leveraging Perl's strong text processing and web fetching capabilities. The primary motivation was to provide a simple, <b>tail</b>-like interface for monitoring dynamic web content, mirroring the utility of <b>tail -f</b> for log files.<br><br>While not as widely known as general-purpose CLI tools, it filled a niche for developers, sysadmins, and command-line enthusiasts who needed quick, scriptable access to feed updates without the overhead of a full-fledged reader. Its development has been community-driven, with various versions and forks available over the years.


title: SEE ALSO
content:
<b>tail</b>(1), <b>curl</b>(1), <b>wget</b>(1), <b>grep</b>(1), <b>newsboat</b>(1), <b>newsbeuter</b>(1)


title: PARAMETERS
content:
<b>-a, --auto-correct</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Automatically correct offenses whenever possible. This is a powerful feature for quick fixes.<br><br><b>--auto-gen-config</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Generate a configuration file (`.rubocop_todo.yml`) based on current offenses, allowing you to gradually fix issues.<br><br><b>--config <file></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specify a custom configuration file to use instead of the default `.rubocop.yml`.<br><br><b>--display-cop-names</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Display the name of the cop that triggered each offense in the output.<br><br><b>--format <formatter></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Choose an output formatter (e.g., `simple`, `progress`, `json`, `html`). Defaults to `progress`.<br><br><b>-o, --out <file></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Write the output of the analysis to the specified file instead of standard output.<br><br><b>--only <cop1,cop2,...></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Run only the specified cops. Useful for focusing on particular rule sets.<br><br><b>--except <cop1,cop2,...></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Run all cops except the specified ones.<br><br><b>--parallel</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Run cops in parallel, which can significantly speed up analysis on large codebases.<br><br><b>--show-cops [cop1,cop2,...]</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Display details about all available cops or specific cops, including their description and configuration options.<br><br><b>--init</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Generate a basic `.rubocop.yml` file in the current directory, helping to quickly set up RuboCop.<br><br><b>-v, --version</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Display the version of RuboCop currently installed.<br><br><b>-h, --help</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Display help information for the `rubocop` command.<br><br>


title: DESCRIPTION
content:
<i>RuboCop</i> is a powerful Ruby static code analyzer and code formatter that enforces the community-driven <I>Ruby Style Guide</I>. It helps maintain consistency, improve code quality, and reduce common errors in Ruby projects. <br><br>It operates by running a series of individual checks, known as 'cops,' which cover various aspects of code, including style, linting, metrics, and security. Users can enable, disable, or configure these cops through a `.rubocop.yml` configuration file, allowing for highly customized enforcement rules tailored to specific project needs or team preferences. <br><br>Beyond simply reporting offenses, <i>RuboCop</i> also offers auto-correction capabilities for many issues, significantly streamlining the code review and refactoring process. It's widely adopted in the Ruby ecosystem and can be easily integrated into development workflows, CI/CD pipelines, and pre-commit hooks.


title: CAVEATS
content:
While highly configurable, <i>RuboCop</i> can sometimes be opinionated, requiring significant adjustments to its configuration file to align with specific project styles not covered by the default style guide. Auto-correction is powerful but not always perfect; it's essential to review changes. Performance can be a concern on very large codebases without parallelization or careful exclusion of files.


title: CONFIGURATION WITH .RUBOCOP.YML
content:
The behavior of <i>RuboCop</i> is primarily controlled by a `.rubocop.yml` file located in the project root or parent directories. This YAML file allows users to enable/disable specific cops, customize their parameters, exclude files or directories from analysis, and inherit configurations from other `.rubocop.yml` files (e.g., from shared style guides). This flexibility is key to adapting <i>RuboCop</i> to diverse project requirements.


title: UNDERSTANDING 'COPS'
content:
In <i>RuboCop</i>, a 'cop' is an individual rule or check. Cops are organized into departments, such as <b>Style</b> (e.g., `Style/HashSyntax`), <b>Lint</b> (for potential errors, e.g., `Lint/UselessAssignment`), <b>Metrics</b> (for code complexity, e.g., `Metrics/MethodLength`), and <b>Security</b> (for potential vulnerabilities, e.g., `Security/Eval`). Each cop checks for a specific aspect of code quality or style, and many offer auto-correction capabilities.


title: HISTORY
content:
<i>RuboCop</i> was created by <b>Bozhidar Batsov</b> and first released in 2012. It quickly gained traction within the Ruby community due to its adherence to the widely accepted <I>Ruby Style Guide</I> and its comprehensive set of checks. It evolved to become the de facto standard for Ruby code style enforcement and static analysis, continually maintained and improved by a vibrant open-source community.


title: SEE ALSO
content:
git(1) (for pre-commit hooks), rake(1) (often used to integrate RuboCop tasks), eslint(1) (JavaScript linter), flake8(1) (Python linter)


title: PARAMETERS
content:
<b>--debug</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Display detailed debugging information about the process.<br><br><b>--view</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Perform the 'view' action. This is the default action if none is specified.<br><br><b>--compose</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Perform the 'compose' action, typically for creating new content of the specified type.<br><br><b>--print</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Perform the 'print' action, to send the file to a printer.<br><br><b>--edit</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Perform the 'edit' action, to open the file in an editor.<br><br><b>--raw</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Do not interpret special '%s' or other '%'-sequences in the mailcap command, passing them literally.<br><br><b>--action=ACTION</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specify the desired action to perform (e.g., 'view', 'compose', 'print', 'edit'). Overrides default.<br><br><b>--no-warn</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Suppress warnings if no suitable program or mailcap entry is found for the given MIME type.<br><br><b>--norun</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Print the command that would be executed, but do not actually run it. Useful for debugging.<br><br><b>--remove-ext</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Remove the filename extension from the file before passing it to the program (often used with '%s').<br><br><b>--no-email-view</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Do not use generic 'text/plain' viewers for email body parts, even if the mailcap entry allows it.<br><br><b>--force-mime=MIMETYPE</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Force the input file to be treated as the specified MIME type, overriding any autodetection.<br><br>


title: DESCRIPTION
content:
<i>run-mailcap</i> is a crucial Linux command-line utility designed to handle non-text files in a MIME-aware manner. It serves as an interpreter for <br><b>mailcap</b> configuration files, which specify how different MIME types (e.g., <i>image/jpeg</i>, <i>application/pdf</i>) should be processed or displayed. <br><br>When invoked, <i>run-mailcap</i> reads through a hierarchical set of mailcap files, typically starting with the user-specific <i>~/.mailcap</i>, followed by system-wide files like <i>/etc/mailcap</i>. It searches for an entry that matches the given MIME type and action (such as view, compose, print, or edit). Upon finding a match, it constructs and executes an external command specified in that mailcap entry, passing the file as an argument. <br><br>This utility is widely used by applications that need to interact with various file formats, including email clients, web browsers, and file managers. For instance, an email client might use <i>run-mailcap</i> to open an attached PDF document in a PDF viewer, or a web browser could use it to launch an external application for a specific media type. Its primary purpose is to abstract away the details of handling diverse file formats by relying on a centralized, configurable system.


title: CAVEATS
content:
<b>Security Risk</b>: <i>run-mailcap</i> executes arbitrary commands defined in mailcap files. Users should exercise caution, especially with custom <i>~/.mailcap</i> configurations or when processing files from untrusted sources, as malicious entries could execute harmful commands.<br><br><b>External Dependencies</b>: Its functionality heavily relies on external programs being installed and accessible in the system's PATH. If a configured viewer/editor is missing, <i>run-mailcap</i> will fail to open the file.<br><br><b>Mailcap Complexity</b>: The underlying <i>mailcap</i> file format can be intricate, involving conditional logic and special sequences. Misconfigurations can lead to unexpected behavior or security vulnerabilities.


title: MAILCAP FILE ORDER
content:
<i>run-mailcap</i> typically consults multiple <i>mailcap</i> files in a specific order to determine the appropriate command. It usually checks the user-specific <i>~/.mailcap</i> first, followed by system-wide files like <i>/etc/mailcap</i>. The first matching entry found for a given MIME type and action is used, providing a mechanism for user overrides.


title: SPECIAL SEQUENCES IN MAILCAP ENTRIES
content:
<i>mailcap</i> entries can include special percent ('%') sequences that act as placeholders for information to be passed to the executed command. Common sequences include <i>%s</i> (for the filename), <i>%t</i> (for the MIME type), and <i>%F</i> (for a list of filenames). Understanding these sequences is crucial for correctly configuring <i>mailcap</i> entries and ensuring the external program receives the necessary arguments.


title: HISTORY
content:
The <i>mailcap</i> specification (RFC 1524), which <i>run-mailcap</i> implements, dates back to 1993. It was created to provide a standardized, configurable way for MIME-aware applications (like early email clients and web browsers) to handle diverse non-textual data types. <i>run-mailcap</i> emerged as a common utility to utilize these configuration files, simplifying the process of invoking external viewers or editors based on a file's MIME type. Its development is intertwined with the evolution of desktop environments and internet applications that required robust MIME handling capabilities.


title: PARAMETERS
content:
<b><b>-t</b> <i>&lt;seconds&gt;</i>, <b>--time-limit=</b><i>&lt;seconds&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets the maximum CPU time (in seconds) the command is allowed to use. If the limit is exceeded, the command is terminated.<br><br><b><b>-r</b> <i>&lt;seconds&gt;</i>, <b>--real-time-limit=</b><i>&lt;seconds&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets the maximum wall-clock time (in seconds) the command is allowed to run. This measures the actual time elapsed, regardless of CPU usage.<br><br><b><b>-m</b> <i>&lt;bytes&gt;</i>, <b>--memory-limit=</b><i>&lt;bytes&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets the maximum memory (in bytes) the command is allowed to allocate. This typically refers to virtual memory, but <b>runlim</b> often monitors resident set size (RSS) as well. Use suffixes like 'K', 'M', 'G' for kilobyte, megabyte, gigabyte.<br><br><b><b>-o</b> <i>&lt;file&gt;</i>, <b>--output-file=</b><i>&lt;file&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Redirects the resource usage statistics and status information to the specified file instead of standard error.<br><br><b><b>-v</b>, <b>--verbose</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Enables verbose output, providing more detailed information about the execution and resource monitoring process.<br><br><b><b>-p</b> <i>&lt;seconds&gt;</i>, <b>--patience=</b><i>&lt;seconds&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the time (in seconds) <b>runlim</b> will wait for the child process to exit cleanly after sending it a termination signal (due to a limit being exceeded).<br><br><b><b>--exit-code-if-timeout=</b><i>&lt;CODE&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets a custom exit code for <b>runlim</b> itself if the executed command exceeds its time limit.<br><br><b><b>--exit-code-if-memoryout=</b><i>&lt;CODE&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets a custom exit code for <b>runlim</b> itself if the executed command exceeds its memory limit.<br><br><b><b>--version</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays the version information of the <b>runlim</b> utility.<br><br><b><b>--help</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays a help message with available options and usage.<br><br>


title: DESCRIPTION
content:
<b>runlim</b> is a utility designed to execute a specified command while imposing and monitoring various resource limits. It can enforce limits on <b>CPU time</b>, <b>wall-clock time</b>, and <b>memory consumption</b> (both virtual and resident set size). Upon completion, it reports the actual resources used by the command and its children.<br><br>This tool is particularly useful in environments like competitive programming, automated assessment systems, or scientific computing where it's crucial to prevent programs from consuming excessive resources or running indefinitely. It provides a robust way to ensure that submitted solutions or experiments adhere to predefined constraints, preventing resource exhaustion on shared systems and facilitating fair evaluation based on resource efficiency.


title: CAVEATS
content:
<b>runlim</b> relies on system calls like <b>setrlimit()</b> and <b>getrusage()</b>, which can have system-specific behaviors or limitations. <br><br>While it monitors both CPU time and wall-clock time, the precision of these measurements can be affected by system load and kernel scheduler activity. <br><br>Memory limits primarily refer to virtual memory; ensuring a strict limit on resident set size (RSS) can be more complex and might not always be perfectly enforced by <b>runlim</b> directly through system limits, though it usually reports RSS. <br><br>Be aware that if the monitored command spawns long-running background processes (daemons) that detach from the parent, <b>runlim</b> might not track their resource usage effectively after the parent process exits. <br><br>If the command being executed catches and handles termination signals (e.g., <b>SIGTERM</b>) and doesn't exit promptly, <b>runlim</b> might eventually resort to sending a more forceful <b>SIGKILL</b> (controlled by the <b>--patience</b> option).


title: EXIT CODES
content:
<b>runlim</b> provides specific exit codes to indicate the outcome of the executed command. <br><br>If the command finishes successfully without exceeding any limits, <b>runlim</b> usually exits with the same exit code as the executed command. <br><br>If a limit (time, memory) is exceeded, <b>runlim</b> will terminate the command and exit with a non-zero status, often a specific code (e.g., 124 for timeout, 125 for memory limit, though this can be customized with <b>--exit-code-if-timeout</b> and <b>--exit-code-if-memoryout</b>). This allows scripts to differentiate between a program's normal failure and a resource-limit violation.


title: HISTORY
content:
<b>runlim</b> is not a standard utility found in all Unix-like systems' default installations, but it is widely used in specific contexts. It was developed primarily for competitive programming platforms, automated judging systems, and academic research environments where precise resource monitoring and strict enforcement of limits are critical. Its design focuses on providing reliable statistics and control over a program's execution, addressing limitations of simpler tools like <b>time(1)</b> or shell <b>ulimit</b> commands, especially regarding real-time and memory tracking for child processes.


title: PARAMETERS
content:
<b><b>-h</b>, <b>--help</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Display help information and usage details for the <i>rustup check</i> command.<br><br><b><b>-v</b>, <b>--verbose</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Enable verbose output, providing more detailed information about the update check process and results.<br><br><b><b>-q</b>, <b>--quiet</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Suppress non-essential messages and warnings, resulting in a quieter output during the check.<br><br><b><b>--version</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Print the version information of the <i>rustup-check</i> utility being used.<br><br><b><b>--no-self-update</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;A global <i>rustup</i> option that prevents <i>rustup</i> from attempting to update itself before executing the check command.<br><br>


title: DESCRIPTION
content:
<i>rustup check</i> is a subcommand of the <i>rustup</i> toolchain manager, which is the official and recommended way to install and manage Rust toolchains on various operating systems. This command systematically scans all installed Rust toolchains (e.g., <i>stable</i>, <i>beta</i>, <i>nightly</i>) and their associated components (such as <i>rustc</i>, <i>cargo</i>, <i>rust-std</i>, and <i>rust-docs</i>) to determine if newer versions or updates are available. It provides a concise summary of pending updates for both the toolchains themselves and for the <i>rustup</i> utility.<br><br>It is important to note that <i>rustup check</i> is purely informational. It identifies and reports available updates but does not automatically perform any installations or upgrades. To apply the detected updates, users typically need to explicitly run the <i>rustup update</i> command. This informational capability makes <i>rustup check</i> an invaluable tool for Rust developers to stay informed about the latest releases and available patches without committing to an immediate system-wide upgrade.


title: CAVEATS
content:
<b>1. Internet Connection Required:</b> This command requires an active internet connection to query official Rust update servers for the latest toolchain and component versions.<br><br><b>2. Informational Only:</b> It only reports available updates and does not perform any actual installations or upgrades. To apply updates, you must explicitly run <i>rustup update</i>.<br><br><b>3. Command Invocation:</b> While the prompt explicitly mentions "<i>rustup-check</i>", the standard and common user-facing invocation is typically "<i>rustup check</i>" as a subcommand of the main <i>rustup</i> utility.


title: UPDATE SOURCE
content:
<i>rustup</i> fetches update information from official Rust project servers, primarily <i>static.rust-lang.org</i>, ensuring reliable and secure update data.


title: NON-DESTRUCTIVE OPERATION
content:
This command is safe to run frequently as it only reads update availability information and does not alter the existing Rust installation, making it ideal for regular monitoring without side effects.


title: HISTORY
content:
<i>rustup</i> was developed to simplify and standardize the installation and management of Rust toolchains (stable, beta, nightly releases) across various operating systems, quickly becoming the official installer for Rust. The <i>check</i> subcommand was introduced as a non-intrusive mechanism to allow Rust developers to monitor for available updates. This functionality empowers users to stay informed about new Rust releases and component updates without immediately triggering an upgrade, giving them control over when to perform actual updates. Its continuous development is tightly integrated with the broader Rust project's release cycle.


title: SYNOPSIS
content:
<b>curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh</b> [<i>OPTIONS</i>]<br><b>./rustup-init.sh</b> [<i>OPTIONS</i>]


title: PARAMETERS
content:
<b><b>-y</b>, <b>--no-confirm</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Proceed with the default installation options without requiring interactive confirmation from the user.<br><br><b><b>--no-modify-path</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Prevent the script from modifying the shell's PATH environment variable. Users will need to manually add <I>$HOME/.cargo/bin</I> to their PATH.<br><br><b><b>--default-host</b> <I>host-triple</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specify the default host triple for the installation, such as <I>x86_64-unknown-linux-gnu</I>.<br><br><b><b>--default-toolchain</b> <I>toolchain-name</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Set the default toolchain to install (e.g., <I>stable</I>, <I>beta</I>, <I>nightly</I>, or a specific version like <I>1.78.0</I>).<br><br><b><b>--profile</b> <I>profile-name</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Select an installation profile: <I>default</I> (rustc, cargo, std), <I>minimal</I> (rustc, cargo), or <I>complete</I> (all available components).<br><br><b><b>--component</b> <I>component-name</I>, <b>--add-component</b> <I>component-name</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Install a specific component (e.g., <I>rust-docs</I>, <I>rustfmt</I>, <I>clippy</I>). This option can be specified multiple times.<br><br><b><b>--target</b> <I>target-triple</I>, <b>--add-target</b> <I>target-triple</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Add a specific target for cross-compilation (e.g., <I>wasm32-unknown-unknown</I>). This option can be specified multiple times.<br><br><b><b>-v</b>, <b>--verbose</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Enable verbose output to display more detailed information during the installation process.<br><br><b><b>--version</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Display the version information for the <I>rustup-init.sh</I> script and exit.<br><br><b><b>-h</b>, <b>--help</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Show the help message for the script and exit.<br><br><b><b>--force</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Force the installation, even if <I>rustup</I> is already detected on the system. Useful for re-installations or updates.<br><br>


title: DESCRIPTION
content:
The <I>rustup-init.sh</I> script is the official bootstrap installer for <I>rustup</I>, the powerful Rust toolchain installer. It streamlines the process of downloading and configuring the Rust programming language environment on Unix-like operating systems, including Linux and macOS. <br><br>When executed, the script typically initiates an interactive installation, guiding the user to select a default Rust toolchain (e.g., stable, beta, nightly), essential components (such as the Rust compiler <I>rustc</I>, the package manager <I>cargo</I>, and documentation), and whether to automatically modify the system's PATH environment variable for ease of use. <br><br>For automated or non-interactive setups, <I>rustup-init.sh</I> is highly configurable. It supports a variety of command-line arguments and environment variables that allow pre-defining installation choices, making it ideal for integration into CI/CD pipelines or system provisioning scripts. By default, it installs Rust and Cargo to the user's home directory (<I>~/.cargo</I>) and updates shell configuration files to include <I>~/.cargo/bin</I> in the PATH, enabling immediate access to Rust's command-line tools.


title: CAVEATS
content:
The <I>rustup-init.sh</I> script requires an active internet connection to download Rust components and toolchains.<br><br>By default, the script modifies common shell profile files (e.g., <I>.bashrc</I>, <I>.zshrc</I>) to add <I>$HOME/.cargo/bin</I> to your PATH. If you use a non-standard shell setup or prefer manual PATH configuration, use the <I>--no-modify-path</I> option.<br><br>While <I>rustup-init.sh</I> handles most Rust-specific dependencies, ensure your system has fundamental build tools (like <I>gcc</I> or <I>clang</I>) installed, as they might be required for compiling certain Rust projects or native extensions.


title: NON-INTERACTIVE INSTALLATION
content:
For automated environments such as Docker containers or CI/CD pipelines, combine the <I>-y</I> (or <I>--no-confirm</I>) option with specific <I>--default-toolchain</I>, <I>--profile</I>, <I>--component</I>, and <I>--target</I> flags. Alternatively, many options can be passed via environment variables prefixed with <I>RUSTUP_INIT_</I> (e.g., <I>RUSTUP_INIT_DEFAULT_TOOLCHAIN=nightly</I>, <I>RUSTUP_INIT_NO_MODIFY_PATH=1</I>).


title: PROXY CONFIGURATION
content:
If your system is located behind an HTTP/HTTPS proxy, it is essential to set the <I>http_proxy</I> and/or <I>https_proxy</I> environment variables correctly before executing the script. The underlying <I>curl</I> command used by the script respects these proxy settings.


title: UNINSTALLATION
content:
To completely remove Rust and <I>rustup</I> from your system, use the <I>rustup</I> command that was installed: <I>rustup self uninstall</I>. This command will intelligently remove the <I>.cargo</I> and <I>.rustup</I> directories from your home folder and reverse any modifications made to your shell configuration files during installation.


title: HISTORY
content:
<I>rustup</I> emerged as the de facto standard tool for managing Rust toolchains, succeeding earlier community efforts like <I>multirust</I>. It was developed by the Rust community to address the need for easy management of multiple Rust versions (stable, beta, nightly) and cross-compilation targets. The <I>rustup-init.sh</I> script was introduced as the initial bootstrapping mechanism, designed to simplify the very first installation of <I>rustup</I> itself, making the powerful capabilities of <I>rustup</I> accessible to a wide audience on Unix-like systems.


title: PARAMETERS
content:
<b><b><I>TOOLCHAIN...</I></b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies one or more toolchains to update. If omitted, all installed updatable toolchains (like <i>stable</i>, <i>beta</i>, <i>nightly</i>) will be updated.<br><br><b><b><I>--force-gc</I></b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Forces immediate garbage collection of old and unused toolchains. <i>rustup</i> typically performs this automatically, but this option can be used for an explicit cleanup.<br><br><b><b><I>--no-self-update</I></b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Prevents <i>rustup</i> from updating itself to a newer version. This can be useful in environments where <i>rustup</i>'s binary should remain fixed, such as CI/CD pipelines.<br><br>


title: DESCRIPTION
content:
The <b><I>rustup update</I></b> command is the primary method for keeping your Rust development environment current. It checks for new versions of all installed official Rust toolchains (e.g., <i>stable</i>, <i>beta</i>, <i>nightly</i>), downloads the latest components, and replaces the old ones. Beyond just toolchains, <b><I>rustup update</I></b> also ensures that the <i>rustup</i> utility itself is upgraded to its newest version, providing access to the latest features and bug fixes of the toolchain manager. This command intelligently identifies and updates only what's necessary, making the process efficient. It is essential for accessing the latest Rust features, performance improvements, and security patches.


title: CAVEATS
content:
Requires an active internet connection to download updates. <br>The update process can take significant time and consume bandwidth, especially for the first update or major releases. <br>While <i>rustup</i> is robust, interrupting the update process (e.g., by force-quitting) can lead to an inconsistent state, potentially requiring a reinstallation of affected toolchains or <i>rustup</i> itself.


title: DEFAULT BEHAVIOR
content:
When invoked without any specific toolchain arguments, <b><I>rustup update</I></b> will update all currently installed toolchains that are official releases (e.g., <i>stable</i>, <i>beta</i>, <i>nightly</i>) and also update the <i>rustup</i> binary itself if a new version is available.


title: OFFLINE UPDATES
content:
<b><I>rustup update</I></b> is primarily an online operation. For offline updates, one would typically use <i>rustup-init</i> with pre-downloaded toolchain archives, or set up a local proxy/mirror, which is beyond the scope of a typical <b><I>rustup update</I></b> usage.


title: HISTORY
content:
The <i>rustup</i> tool was developed to streamline the management of Rust toolchains, inspired by similar version managers like <i>nvm</i> and <i>rbenv</i>. The <b><I>rustup update</I></b> command has been a core and foundational part of <i>rustup</i> since its early development, essential for keeping Rust installations current without manual uninstallation and reinstallation steps.


title: SYNOPSIS
content:
<i>s2p</i> [<i>options</i>] <i>device</i> [<i>parameters</i>]<br>Example: <i>s2p</i> <i>/dev/ttyS0</i> <i>9600</i> <i>N81</i>


title: PARAMETERS
content:
<b>-b, --baud <i>rate</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets the baud rate for the serial port (e.g., 9600, 115200).<br><br><b>-d, --data-bits <i>bits</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the number of data bits (commonly 5, 6, 7, or 8).<br><br><b>-p, --parity <i>type</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets the parity type (N for none, O for odd, E for even).<br><br><b>-s, --stop-bits <i>bits</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Defines the number of stop bits (typically 1 or 2).<br><br><b>-f, --flow-control <i>type</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Configures flow control (e.g., none, hardware, software).<br><br><b>-l, --list <i>device</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays the current settings for a specified serial device.<br><br><b>-h, --help</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Shows a help message and exits.<br><br><b>-v, --version</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays version information and exits.<br><br>


title: DESCRIPTION
content:
The <i>s2p</i> command is a hypothetical (or highly specialized) command-line utility conceptualized for basic configuration of serial communication ports (TTY devices) on a Linux system. Its primary purpose would be to streamline common adjustments to serial port settings, such as baud rate, data bits, parity, and stop bits, without requiring the user to delve into more complex or granular tools like <i>stty</i> or <i>setserial</i>. It aims to provide a user-friendly interface for quick setup of serial devices, often used in embedded systems development, hardware interfacing, or legacy system communication scenarios. While <i>setserial</i> and <i>stty</i> offer comprehensive control, <i>s2p</i> would focus on the most frequently modified parameters for rapid deployment and testing of serial connections. Its design would prioritize simplicity and ease of use, making it accessible for users who need to quickly establish or verify serial link parameters for specific applications.


title: CAVEATS
content:
The <b>s2p</b> command is <b>not a standard Linux utility</b> found in most common distributions or <i>coreutils</i>. This analysis is based on a hypothetical command with a name that suggests 'Serial To Parameters' or 'Set Serial Port' functionality, similar to what <i>setserial</i> or <i>stty</i> provide. If you are looking for a tool to manage serial ports, please refer to <i>setserial(8)</i> or <i>stty(1)</i>. The existence and exact functionality of a command named <i>s2p</i> would depend on specific custom installations or niche software packages.


title: COMMON USE CASES (HYPOTHETICAL)
content:
If <i>s2p</i> were to exist, its primary use cases would include:<br><i>- Quick Setup for Embedded Devices:</i> Rapidly configuring a serial port for communication with microcontrollers or single-board computers during development.<br><i>- Debugging Serial Links:</i> Temporarily adjusting serial parameters to match a connected device for troubleshooting communication issues.<br><i>- Automated Scripting:</i> Being used within shell scripts to programmatically set serial port characteristics before initiating data transfer or monitoring.


title: HISTORY
content:
There is no widely documented history for a standard <i>s2p</i> command in Linux. Any utility bearing this name would likely be a custom script or a component of a specialized hardware/software project designed to simplify serial port interactions, potentially as a wrapper around existing tools like <i>termios</i> system calls, <i>stty</i>, or <i>setserial</i>. Its development would be driven by the need for a quick, simplified interface for specific serial communication tasks rather than a general-purpose system tool.


title: SYNOPSIS
content:
<i>s3cmd</i> <b>[OPTIONS]</b> <i>COMMAND</i> <b>[ARGS]</b><br><br>Common commands include:<br>&nbsp;&nbsp;<i>s3cmd</i> <b>ls</b> <i>[s3://BUCKET[/PREFIX]]</i><br>&nbsp;&nbsp;<i>s3cmd</i> <b>put</b> <i>FILE [FILE...] s3://BUCKET[/PREFIX]</i><br>&nbsp;&nbsp;<i>s3cmd</i> <b>get</b> <i>s3://BUCKET/OBJECT [LOCAL_FILE]</i><br>&nbsp;&nbsp;<i>s3cmd</i> <b>sync</b> <i>LOCAL_DIR s3://BUCKET[/PREFIX]</i><br>&nbsp;&nbsp;<i>s3cmd</i> <b>mb</b> <i>s3://BUCKET</i><br>&nbsp;&nbsp;<i>s3cmd</i> <b>rb</b> <i>s3://BUCKET</i>


title: PARAMETERS
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<b><b>--configure</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Launches an interactive wizard to set up access keys and other configuration options for S3 access.<br><br><b><b>--force</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Performs the action without asking for confirmation, useful for scripting.<br><br><b><b>--dry-run</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Simulates the command execution and displays what actions would be taken without actually performing them.<br><br><b><b>-r</b>, <b>--recursive</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Applies the command recursively to all files and subdirectories within a specified path.<br><br><b><b>--acl-public</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets the Access Control List (ACL) of uploaded objects to public-read, making them accessible to anyone via their URL.<br><br><b><b>--delete-removed</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;(Used with <i>sync</i>) Deletes files in the destination S3 bucket that do not exist in the source directory.<br><br><b><b>--encrypt</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Encrypts uploaded objects on the S3 server side using S3-managed encryption keys (SSE-S3).<br><br><b><b>--add-header=HEADER:VALUE</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Adds a custom HTTP header to the S3 request, useful for setting metadata or specific S3 options.<br><br>


title: DESCRIPTION
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<i>s3cmd</i> is a powerful command-line tool designed for interacting with Amazon Simple Storage Service (S3) and other S3-compatible object storage solutions, such as Google Cloud Storage, Ceph, and MinIO. It provides a comprehensive set of functionalities to manage data stored in the cloud. Users can perform essential operations like uploading files and entire directories, downloading objects, synchronizing local directories with S3 buckets, listing bucket contents, creating and deleting buckets, and managing object permissions (ACLs). <i>s3cmd</i> supports advanced features like multipart uploads for large files, encryption, and the ability to configure multiple profiles for different storage accounts. Its intuitive syntax and robust capabilities make it an excellent choice for scripting automated backups, data transfers, and general cloud storage administration tasks directly from the Linux command line. It's widely used by developers and system administrators for efficient data management in cloud environments.


title: CAVEATS
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<i>s3cmd</i> relies heavily on its configuration file (typically <i>~/.s3cfg</i>) for authentication credentials and default settings; incorrect or missing configuration will prevent operation. While functional, it might not support the very latest S3 features or regional nuances as quickly as AWS's official command-line tools. For large-scale operations or complex S3 features (e.g., advanced Glacier operations, S3 Select), the official <i>AWS CLI</i> might offer more comprehensive support and performance.


