# CommandSection

title: SECURITY IMPLICATIONS
content:
Due to its age, NIS was designed without modern security considerations. Data transmitted via NIS, including sensitive information like password hashes (if not using shadow passwords), is often in <b>plain text</b>. This makes it susceptible to <b>eavesdropping, spoofing, and data manipulation</b> if not operated within a highly trusted and isolated network environment or secured by other means like VPNs.


title: HISTORY
content:
NIS, originally named <b>Yellow Pages (YP)</b> by Sun Microsystems, emerged in the 1980s as a centralized directory service for UNIX-like systems. <i>ypbind</i> has been a fundamental component since its inception, enabling client-server communication. While widely used in the past for managing user accounts, hostnames, and other system data across a network, its adoption has significantly declined due to the rise of more secure, scalable, and feature-rich directory services like <b>LDAP</b>. Despite its legacy status, <i>ypbind</i> still sees use in maintaining older infrastructures.


title: PARAMETERS
content:
<b>N/A</b><br>&nbsp;&nbsp;&nbsp;&nbsp;No parameters can be defined for an unrecognized command.<br><br>


title: DESCRIPTION
content:
The command <i>'yplan'</i> does not appear to be a standard or commonly recognized utility within the Linux operating system. Standard Linux distributions, their core packages, and common open-source projects do not list a command with this name.<br><br>It is possible that <i>'yplan'</i>:<br><b>1.</b> Is a custom script or internal tool specific to a particular environment or organization.<br><b>2.</b> Is a typo for another existing command.<br><b>3.</b> Refers to a component of a niche software package that is not widely documented.<br><br>As such, providing accurate details regarding its syntax, options, or typical usage is not feasible without further context or clarification from the environment where it was observed.


title: CAVEATS
content:
This command is not part of standard Linux utilities. Any system encountering a command named 'yplan' is likely running a custom script or a specialized application that defines it within that specific environment. It should not be expected to function on a generic Linux installation.


title: FURTHER INVESTIGATION RECOMMENDED
content:
If you encountered <i>'yplan'</i> in a specific context (e.g., a script, a project's documentation), please refer to the documentation or source code of that specific project or environment to understand its intended purpose and usage.


title: SYNOPSIS
content:
<b>yq</b> [<i>options</i>] <i><expression></i> [<i><file(s)></i>...] <br> <b>yq</b> [<i>options</i>] <i><command></i> [<i><arguments></i>] [<i><file(s)></i>...]


title: PARAMETERS
content:
<b><b>-i</b>, <b>--inplace</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Edit files in place. Creates a backup file unless <b>--inplace=false</b> is specified.<br><br><b><b>-o</b>, <b>--output-format</b> <i><format></i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Set the output format. Supported formats include: <i>yaml</i>, <i>json</i>, <i>xml</i>, <i>tsv</i>, <i>csv</i>, <i>properties</i>.<br><br><b><b>-p</b>, <b>--prettyPrint</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Pretty print the output. This formats the output for readability.<br><br><b><b>-C</b>, <b>--colors</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Enable colored output for better readability in terminals.<br><br><b><b>-r</b>, <b>--raw-output</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Output raw strings, without quotes for string values.<br><br><b><b>--arg</b> <i><name> <value></i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Pass a string argument to the expression, accessible as <b>$name</b>.<br><br><b><b>--from-file</b> <i><path></i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Read the <b>yq</b> expression from the specified file.<br><br>


title: DESCRIPTION
content:
<b>yq</b> is a portable command-line YAML, JSON, XML, TOML, CSV, and properties processor, often referred to as '<i>jq</i> for YAML'. It provides a powerful and intuitive way to query, update, and transform structured data files directly from the terminal. Unlike traditional text processing tools, <b>yq</b> understands the underlying data structure, allowing for precise manipulation of elements based on their hierarchical path. <br><br> Its primary use cases include extracting specific values from configuration files, modifying Kubernetes manifests, converting data between different formats (e.g., YAML to JSON), and programmatically updating various structured documents. <b>yq</b>'s syntax is inspired by <i>jq</i>, making it familiar to users already comfortable with JSON processing. It supports in-place editing, making it invaluable for scripting automated file modifications. Its ability to handle multiple input files and stream processing further enhances its utility for complex data workflows. <b>yq</b> is an essential tool for DevOps engineers, developers, and anyone working extensively with configuration or data files in a variety of structured formats.


title: CAVEATS
content:
It's important to note that there are multiple tools named 'yq'. This analysis refers specifically to the <b>mikefarah/yq</b> project, which is widely adopted for its robust features and active development. A common caveat is that in-place editing (<b>-i</b>) can sometimes reformat comments or change the ordering of map keys, although efforts are continually made to preserve them. Complex YAML anchors and aliases might also behave unexpectedly during certain modification operations, or be lost entirely when rewriting files.


title: COMMON USE CASES
content:
Extracting and manipulating values from YAML/JSON configuration files. <br> Automating modifications to Kubernetes manifests. <br> Converting data between YAML, JSON, XML, TOML, and other supported formats. <br> Filtering and transforming structured logs or data streams.


title: INSTALLATION
content:
<b>yq</b> is typically distributed as a single static binary, making installation straightforward. It can often be installed via popular package managers like Homebrew (macOS/Linux), Scoop (Windows), or directly downloaded from its GitHub releases page. <br><br> For example, on macOS you can use: <i>brew install yq</i>


title: HISTORY
content:
<b>yq</b> emerged as a versatile command-line tool to fill the gap for a robust YAML processor, much like <b>jq</b> serves for JSON. The <b>mikefarah/yq</b> implementation, developed by Mike Farah, quickly gained prominence due to its comprehensive feature set, cross-platform compatibility, and ability to handle complex YAML structures, including in-place editing. Its design philosophy aimed for <i>jq</i>-like syntax and power, making it an indispensable tool for modern infrastructure and data management workflows.


title: SYNOPSIS
content:
<b>yt-dlp</b> [<i>OPTIONS</i>] <i>URL</i> [<i>URL...</i>]<br><br>Common usage examples:<br><b>yt-dlp</b> <i>https://www.youtube.com/watch?v=VIDEO_ID</i><br><b>yt-dlp -f bestvideo[ext=mp4]+bestaudio[ext=m4a] -o "%(title)s.%(ext)s"</b> <i>URL</i><br><b>yt-dlp --extract-audio --audio-format mp3</b> <i>URL</i><br><b>yt-dlp --write-subs --all-subs --embed-subs</b> <i>URL</i>


title: PARAMETERS
content:
<b>-f, --format FORMAT</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Selects the desired video and/or audio format.<br><br><b>-o, --output TEMPLATE</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the output filename template.<br><br><b>-x, --extract-audio</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Extracts only the audio from the video.<br><br><b>--audio-format FORMAT</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the audio format to convert to when extracting audio (e.g., mp3, aac).<br><br><b>--write-subs, --write-auto-subs</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Downloads available subtitles or auto-generated captions.<br><br><b>--all-subs</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Downloads all available subtitles for the video.<br><br><b>--embed-subs</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Embeds subtitles into the video file (requires <i>ffmpeg</i>).<br><br><b>--write-thumbnail</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Downloads the video thumbnail.<br><br><b>--embed-thumbnail</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Embeds the thumbnail into the video file.<br><br><b>--ignore-errors</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Continues downloading other videos in a playlist even if one fails.<br><br><b>--playlist-start NUMBER</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Starts downloading a playlist from a specific entry.<br><br><b>--playlist-end NUMBER</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Ends downloading a playlist at a specific entry.<br><br><b>--abort-on-error</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Aborts the entire operation if a download error occurs.<br><br><b>--restrict-filenames</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Restricts filenames to only ASCII characters and avoids special characters.<br><br><b>--dump-json</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Prints video information in JSON format and does not download.<br><br><b>-U, --update</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Updates the <i>yt-dlp</i> executable to the latest version.<br><br><b>-v, --verbose</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Prints verbose debugging information.<br><br><b>--proxy URL</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Uses a specified HTTP/SOCKS proxy.<br><br><b>--user-agent UA</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies a custom User-Agent header.<br><br><b>--force-ipv4, --force-ipv6</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Forces <i>yt-dlp</i> to use IPv4 or IPv6 respectively.<br><br>


title: DESCRIPTION
content:
<i>yt-dlp</i> is a free and open-source command-line program for downloading videos and audio from over 1000 websites. It is a fork of the popular <i>youtube-dl</i> project, created to address its slower development pace and to introduce new features and improvements.<br><br>It offers extensive customization options for video and audio formats, resolution, quality, and output filenames. Key features include support for playlists, entire channels, embedding metadata, downloading subtitles (including auto-generated ones), and integrating with external tools like <i>ffmpeg</i> for post-processing (e.g., converting formats, extracting audio). <i>yt-dlp</i> also boasts advanced features such as SponsorBlock integration for skipping unwanted segments, parallel downloads, and the ability to handle various authentication methods. Its robust nature and active development make it a versatile tool for media acquisition, respecting user-defined preferences and offering granular control over the download process.


title: CAVEATS
content:
Legal and ethical considerations: Downloading copyrighted material without permission may be illegal in some jurisdictions. Users are responsible for ensuring their usage complies with copyright laws and terms of service of the respective platforms.<br><br>Reliance on external tools: For certain features like format conversion, embedding, or specific post-processing, <i>yt-dlp</i> often requires <i>ffmpeg</i> or <i>ffprobe</i> to be installed and accessible in the system's PATH.<br><br>Website changes: Video hosting sites frequently update their structures and APIs, which can sometimes temporarily break <i>yt-dlp</i>'s ability to download from them until an update is released.


title: CONFIGURATION FILE
content:
Users can create a configuration file (typically <i>~/.config/yt-dlp/config</i> or <i>~/.yt-dlp.conf</i>) to define default options and arguments that <i>yt-dlp</i> will use every time it runs. This is useful for consistently applying preferred settings without typing them out for each command.


title: SPONSORBLOCK INTEGRATION
content:
<i>yt-dlp</i> includes native support for SponsorBlock, allowing users to automatically skip sponsored segments, introductions, outros, and other unwanted parts of videos during playback or even during the download process itself by applying post-processing.


title: HISTORY
content:
<i>yt-dlp</i> emerged as a fork of the widely used <i>youtube-dl</i> project. The motivation behind its creation was the perceived stagnation of <i>youtube-dl</i>'s development, with long-standing issues and feature requests going unaddressed. The <i>yt-dlp</i> project aimed to provide a more actively maintained and feature-rich alternative, quickly integrating new extractors, bug fixes, and advanced functionalities like SponsorBlock and parallel downloads. It has since gained significant popularity and is now often recommended as the preferred choice over its predecessor due to its robust and up-to-date capabilities.


title: PARAMETERS
content:
<b>-t <query></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Perform a search for the given query.<br><br><b>-L</b><br>&nbsp;&nbsp;&nbsp;&nbsp;List trending videos.<br><br><b>-H <channel_url></b><br>&nbsp;&nbsp;&nbsp;&nbsp;List videos from a specific YouTube channel URL.<br><br><b>-h</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Display help message and exit.<br><br><b>-m</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Play video only (no audio).<br><br><b>-a</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Play audio only.<br><br><b>-i</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Enable interactive mode (default for searches).<br><br><b>-s</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Perform a strict search without using <i>fzf</i> for selection.<br><br><b>-D</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Download the selected video instead of playing it.<br><br><b>-u</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Update the <i>ytfzf</i> script to the latest version.<br><br><b>-o <mpv_options></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Pass additional options directly to <i>mpv</i> (or the configured player).<br><br><b>-f <format_code></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specify the video/audio format code to download/play (e.g., <i>bestaudio</i>, <i>bestvideo[height<=720]</i>).<br><br><b>-l</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Loop the selected video indefinitely.<br><br><b>-c</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Clear <i>ytfzf</i>'s cache.<br><br><b>-C <cache_dir></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specify a custom directory for <i>ytfzf</i>'s cache.<br><br><b>-x</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Open the selected video in the default web browser instead of playing it in <i>mpv</i>.<br><br><b>-p <playlist_url></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Search within a specific YouTube playlist URL.<br><br><b>-S <sort_order></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sort search results. Common values include <i>date</i>, <i>rating</i>, <i>relevance</i>, <i>views</i>.<br><br><b>-U</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Use an unofficial YouTube API for search.<br><br><b>-M</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Use minimal output for <i>fzf</i> (show only titles).<br><br><b>-v</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Enable verbose output for debugging.<br><br><b>--proxy <proxy_url></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Use a proxy for network requests.<br><br><b>--version</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Display the version of <i>ytfzf</i> and exit.<br><br>


title: DESCRIPTION
content:
ytfzf is a powerful command-line utility that brings the YouTube experience to your terminal. It leverages <b>fzf</b> for interactive fuzzy searching of YouTube videos and uses <b>youtube-dl</b> or <b>yt-dlp</b> to fetch video information, with <b>mpv</b> for playback. Users can quickly search for videos, browse trending content, or access channel videos directly from their shell, then play them, download them, or even extract just the audio. Its interactive nature, powered by <b>fzf</b>, allows for efficient navigation and selection of results, making it a favorite for those who prefer a keyboard-driven workflow. ytfzf abstracts away the complexities of underlying command-line arguments, providing a streamlined interface.


title: CAVEATS
content:
<i>ytfzf</i> relies on several external dependencies to function correctly:<br> - <b><i>fzf</i></b>: For interactive fuzzy searching. Without it, only strict search (<i>-s</i>) is possible.<br> - <b><i>mpv</i></b> (or an alternative video player): For playing videos.<br> - <b><i>youtube-dl</i></b> or <b><i>yt-dlp</i></b>: For fetching video information and streams from YouTube.<br>Ensure these dependencies are installed and accessible in your system's PATH. Performance may vary based on network speed and API rate limits.


title: DEPENDENCIES
content:
<i>ytfzf</i> requires <i>fzf</i>, <i>mpv</i> (or an alternative player like <i>vlc</i>), and <i>youtube-dl</i> or <i>yt-dlp</i> to be installed on your system. It will typically check for <i>yt-dlp</i> first, then <i>youtube-dl</i>.


title: CONFIGURATION
content:
Users can customize <i>ytfzf</i>'s behavior through environment variables or by editing the script directly. For instance, <i>YTFZF_DEFAULT_PLAYER</i> can be set to use a player other than <i>mpv</i>.


title: WORKFLOW
content:
The typical workflow involves running <i>ytfzf -t "your search query"</i>, which presents a <i>fzf</i> interface of results. You can then fuzzy-find, select a video (often by pressing Enter), and <i>ytfzf</i> will launch <i>mpv</i> to play it.


title: HISTORY
content:
<i>ytfzf</i> emerged from the desire for a more interactive and terminal-centric way to browse and play YouTube videos, leveraging the power of <i>fzf</i> for a superior user experience compared to directly piping <i>youtube-dl</i> output. It's an open-source project, primarily developed on GitHub, and benefits from community contributions, continually adding new features and improving compatibility with YouTube's evolving platform and <i>youtube-dl</i>/<i>yt-dlp</i> updates. Its development reflects the Linux community's preference for lightweight, modular tools that can be composed to achieve complex workflows.


title: PARAMETERS
content:
<b>--add-repo=URL</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Adds a new repository definition from the specified URL to the system's configuration. The URL should point to a .repo file.<br><br><b>--disable=REPOID</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Disables the specified repository or a comma-separated list of repository IDs. Wildcards are supported.<br><br><b>--enable=REPOID</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Enables the specified repository or a comma-separated list of repository IDs. Wildcards are supported.<br><br><b>--setopt=OPTION=VALUE</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets a specific option for a repository or globally. E.g., <i>--setopt=reponame.enabled=0</i> or <i>--setopt=timeout=120</i>.<br><br><b>--save</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Saves the current configuration changes to the respective .repo files, making them persistent across reboots.<br><br><b>--dump</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays the current repository configuration, including enabled/disabled status and other options, without making changes.<br><br><b>--all-enablerepo</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Enables all currently configured repositories.<br><br><b>--all-disablerepo</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Disables all currently configured repositories.<br><br>


title: DESCRIPTION
content:
The <i>yum-config-manager</i> command, part of the <i>yum-utils</i> package, provides a convenient way to manage Yum and DNF repository configurations. It allows users to enable or disable repositories, add new ones, and modify various repository options directly from the command line. This command primarily manipulates the .repo files located in <i>/etc/yum.repos.d/</i>, making it an essential tool for system administrators to control where their systems retrieve software packages. While originally designed for Yum, on modern systems it often acts as an alias or wrapper for <i>dnf config-manager</i>, adapting to the DNF package manager.


title: CAVEATS
content:
On modern Red Hat based systems (e.g., RHEL 8+, Fedora), <i>yum-config-manager</i> is typically an alias or symlink to <i>dnf config-manager</i>. For new scripts or configurations, it's generally recommended to use <i>dnf config-manager</i> directly if DNF is the primary package manager.<br>This command requires root privileges to modify system-wide repository configurations. Ensure you understand the source and trustworthiness of any new repositories added, as they can significantly impact system security and stability.


title: COMMON USE CASES
content:
<b>Enabling a specific repository:</b> <i>sudo yum-config-manager --enable epel</i><br><b>Disabling a specific repository:</b> <i>sudo yum-config-manager --disable updates</i><br><b>Adding a new repository from a URL:</b> <i>sudo yum-config-manager --add-repo https://download.fedoraproject.org/pub/epel/epel-release-latest-8.noarch.rpm</i> (Note: This URL points to an RPM that provides the .repo file)<br><b>Viewing current repository configurations:</b> <i>yum-config-manager --dump</i>


title: HISTORY
content:
<i>yum-config-manager</i> originated as part of the <i>yum-utils</i> package, which provided various utilities to complement the Yum package manager. Its primary role was to simplify the management of repository configuration files, often found in <i>/etc/yum.repos.d/</i>. With the widespread adoption of DNF as the default package manager in newer Linux distributions (starting with Fedora and later RHEL 8), the functionality was largely mirrored in <i>dnf-config-manager</i>. Consequently, <i>yum-config-manager</i> often became a compatibility wrapper or an alias, ensuring continuity for existing scripts and user familiarity during the transition.


title: SYNOPSIS
content:
<b>yuvsplittoppm</b> <i>[-w width] [-h height] [-k K] [-c C] [-t] [-g] [-s skip] [-f first] [-l last] [-p prefix] [inputfile]</i>


title: PARAMETERS
content:
<b><b>-w</b> <i>width</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the <i>width</i> of the output image in pixels. This is a mandatory parameter.<br><br><b><b>-h</b> <i>height</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the <i>height</i> of the output image in pixels. This is a mandatory parameter.<br><br><b><b>-k</b> <i>K</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Indicates YUV 4:1:1 format. <i>K</i> typically defines the chroma subsampling (e.g., 4:1:1 or 4:2:2). This option is commonly used for BT.878 capture cards.<br><br><b><b>-c</b> <i>C</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Indicates YUV 4:2:0 format. <i>C</i> typically defines the chroma subsampling.<br><br><b><b>-t</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Transposes the input image (swaps width and height) during conversion.<br><br><b><b>-g</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Generates grayscale (PBM) output instead of color (PPM).<br><br><b><b>-s</b> <i>skip</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Skips the first <i>skip</i> frames from the input YUV stream before processing.<br><br><b><b>-f</b> <i>first</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Starts processing from the <i>first</i> frame number specified.<br><br><b><b>-l</b> <i>last</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Stops processing after the <i>last</i> frame number specified.<br><br><b><b>-p</b> <i>prefix</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies a <i>prefix</i> for the output filenames. The filenames will be <i>prefixNNNNNN</i><b>.ppm</b>.<br><br><b><i>inputfile</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;The path to the input YUV stream file. If omitted, <i>yuvsplittoppm</i> reads from standard input.<br><br>


title: DESCRIPTION
content:
<i>yuvsplittoppm</i> is a utility from the Netpbm project designed to convert raw YUV 4:1:1 (BT.878) or YUV 4:2:0 interleaved video streams into a sequence of PPM (Portable Pixmap) image files.<br><br>It's commonly used to process raw video data captured from sources like video capture cards, allowing each frame of the YUV stream to be extracted and saved as an individual image. This command is crucial for debugging video capture issues or for further processing video frames with other image manipulation tools.<br><br>It handles various YUV sub-sampling formats and allows specifying the output dimensions, frame ranges, and naming conventions for the output PPM files. The tool outputs a separate PPM file for each frame, making it suitable for analyzing individual frames of a video stream.


title: CAVEATS
content:
<ul><li><i>yuvsplittoppm</i> expects raw YUV data, not video container formats like AVI, MP4, or MKV. You'll need to extract the raw YUV stream first if your video is in such a container.</li><li>It primarily supports YUV 4:1:1 (BT.878) and 4:2:0 formats. Other YUV variants might not be correctly interpreted.</li><li>The <b>width</b> and <b>height</b> parameters are crucial and must accurately match the resolution of the YUV stream; otherwise, the output images will be distorted.</li></ul>


title: OUTPUT FILENAMES
content:
<i>yuvsplittoppm</i> generates output files with names like <i>prefixNNNNNN</i><b>.ppm</b>, where <i>NNNNNN</i> is a zero-padded frame number. If no prefix is specified with <b>-p</b>, the default prefix used is 'frame', resulting in filenames like <b>frame000000.ppm</b>.


title: STANDARD INPUT/OUTPUT
content:
The command can read YUV data from standard input if no <i>inputfile</i> is provided, making it suitable for piping from other commands (e.g., <b>dd</b> or <b>cat</b>). Note that it always writes the output PPM files to the filesystem, not to standard output.


title: HISTORY
content:
<i>yuvsplittoppm</i> is part of the Netpbm project, a long-standing toolkit for graphics file format conversion. Netpbm originated from Jef Poskanzer's Pbmplus package, released in 1988. It later evolved into Netpbm, maintained by Bryan Henderson. The <i>yuvsplittoppm</i> command was developed to address the need for processing raw YUV video streams, particularly those originating from early video capture hardware like BT.878 cards, common in the late 1990s and early 2000s for TV tuners and video digitizers. Its development reflects the open-source community's efforts to provide tools for low-level media processing.


title: SYNOPSIS
content:
<b>yuvtoppm</b> [<i>-interlace</i>] [<i>-nofixfloat</i>] [<i>-verbose</i>] [<i>-strict</i>] [<i>-ignorewarnings</i>] [<i>-rawwidth=W</i>] [<i>-rawheight=H</i>] [<i>-rawchromasub=F</i>] [<i>-nframes=N</i>] [<i>-startframe=N</i>] [<i>-output=FILE</i>] [<i>infile</i>]


title: PARAMETERS
content:
<b><i>infile</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Path to the input YUV file. Reads from standard input if omitted.<br><br><b><i>-rawwidth=W</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the width (in pixels) for raw YUV input lacking header information.<br><br><b><i>-rawheight=H</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the height (in pixels) for raw YUV input lacking header information.<br><br><b><i>-rawchromasub=F</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets the chroma subsampling format (e.g., "420", "422", "444") for raw YUV input.<br><br><b><i>-output=FILE</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Writes all output PPM data to the specified file instead of standard output.<br><br><b><i>-nframes=N</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Processes a maximum of N frames from the input stream.<br><br><b><i>-startframe=N</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Begins processing from the Nth frame (0-indexed).<br><br><b><i>-verbose</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays detailed messages about the conversion process to standard error.<br><br><b><i>-strict</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Causes the command to exit with an error if input stream warnings are encountered.<br><br><b><i>-ignorewarnings</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Continues processing despite input stream warnings, overriding <i>-strict</i>.<br><br><b><i>-interlace</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Enables handling for interlaced YUV input streams, converting fields to frames.<br><br><b><i>-nofixfloat</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Disables internal floating-point adjustments for chroma conversion.<br><br>


title: DESCRIPTION
content:
<b>yuvtoppm</b> is a powerful utility designed to convert raw YUV video data into a sequence of PPM (Portable Pixmap) images. It reads YUV input, either from a file or standard input, and outputs the corresponding PPM frames to standard output or a specified file.<br><br>The command intelligently handles the YUV4MPEG2 stream format, which includes embedded header information about video dimensions, frame rate, and chroma subsampling. For raw YUV streams without such headers, users must explicitly specify parameters like width, height, and chroma format using command-line options. This tool is fundamental for workflows involving low-level video processing, allowing users to extract individual frames, manipulate them using image processing tools (like those from the <b>Netpbm</b> suite), or prepare them for re-encoding into other formats. It bridges the gap between raw video data and standard image manipulation pipelines.


title: CAVEATS
content:
<b>yuvtoppm</b> is designed for raw YUV data; it cannot process compressed video formats (e.g., MPEG, H.264).<br>The output is a concatenated stream of PPM images. For individual frame extraction, additional tools like <b>ppmsplit</b> are often required downstream.<br>Color conversion from YUV to RGB (PPM) may involve minor precision losses.


title: INPUT STREAM TYPE
content:
<b>yuvtoppm</b> automatically detects if the input is a YUV4MPEG2 stream (which contains header metadata). If the input is raw YUV data without this header, it is crucial to provide the frame dimensions using the <i>-rawwidth</i> and <i>-rawheight</i> options, and optionally <i>-rawchromasub</i>, to ensure correct interpretation of the video data.


title: PIPELINING
content:
As <b>yuvtoppm</b> reads from standard input and writes to standard output by default, it is highly suitable for use in Unix pipelines. This allows it to be combined with other command-line tools for complex video processing workflows, such as <i>cat video.y4m | yuvtoppm | ppmsplit output_frame_%04d.ppm</i> to extract individual frames.


title: HISTORY
content:
The <b>yuvtoppm</b> utility typically belongs to the <i>yuvtools</i> collection, a suite of programs developed for handling raw YUV video streams. Its origins are closely tied to the early days of open-source multimedia processing on Unix-like systems, often complementing the functionality of the <b>Netpbm</b> image manipulation toolkit. It emerged to address the need for flexible command-line tools capable of converting raw video data into widely supported image formats for further analysis and processing.


title: PARAMETERS
content:
<b><I>width</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;The exact width, in pixels, of the YUY2 image stream being provided to standard input.<br><br><b><I>height</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;The exact height, in pixels, of the YUY2 image stream being provided to standard input.<br><br>


title: DESCRIPTION
content:
The <b>yuy2topam</b> command is a specialized utility within the comprehensive Netpbm image manipulation toolkit. Its primary function is to convert raw YUY2 pixel data, typically streamed from a video source or file, into the Portable Arbitrary Map (PAM) format. YUY2 (also known as YUYV) is a common packed pixel format where chroma (color) information is subsampled horizontally, making it efficient for video storage and transmission. <br><br><b>yuy2topam</b> reads the raw YUY2 data from standard input (stdin) and outputs the converted PAM image to standard output (stdout). This design makes it highly suitable for use in Unix-like pipelines, allowing users to chain it with other Netpbm tools for further processing, such as converting to other image formats (like PNG or JPEG), resizing, or applying various image filters. <br><br>The command requires the exact width and height of the YUY2 input image as command-line arguments to correctly interpret the incoming byte stream. It handles the necessary color space conversion from YUV to RGB as part of its process, producing a standard RGB image in PAM format.


title: CAVEATS
content:
<b>yuy2topam</b> expects raw YUY2 data without any header information. Providing incorrect <I>width</I> or <I>height</I> values will lead to a corrupted or unreadable output image. It assumes a continuous stream of YUY2 frames if used with video, processing only the first frame based on the specified dimensions unless further processing in a loop is managed externally. The command itself does not provide error messages for malformed input beyond what Netpbm might inherently detect during PAM creation.


title: INPUT/OUTPUT STREAMS
content:
This command operates strictly on standard input (stdin) for YUY2 data and standard output (stdout) for the resulting PAM image. This design facilitates its integration into shell scripts and complex data processing pipelines, where it can be combined seamlessly with other commands for data acquisition, manipulation, and storage.


title: COLOR SPACE CONVERSION
content:
YUY2 is a YCbCr (or YUV) color space format, which separates luma (brightness) from chroma (color). <b>yuy2topam</b> automatically performs the necessary conversion from this YCbCr color space to RGB (Red, Green, Blue) as part of its processing. The output PAM file will represent the image in an RGB format, suitable for display or further processing by tools that expect RGB data.


title: HISTORY
content:
<b>yuy2topam</b> is an integral part of the Netpbm project, a long-standing and widely used toolkit for graphics file format conversion. The Netpbm suite originated from Jef Poskanzer's Pbmplus package, first released in 1988, and was later continued as Netpbm in 1993. The philosophy of Netpbm tools is to be small, single-purpose utilities that can be chained together in powerful ways through Unix pipes. <br><br>As video formats and digital imaging became more prevalent, specific converters like <b>yuy2topam</b> were added to handle common raw video pixel formats, extending Netpbm's capability beyond static image files to encompass streams of image data from devices or files. Its development reflects the continuous evolution of the Netpbm project to support a broader range of image and video data types.


title: PARAMETERS
content:
<b><i>keywords</i>...</b><br>&nbsp;&nbsp;&nbsp;&nbsp;One or more space-separated keywords. <i>z</i> will attempt to find the best matching directory based on these keywords and its frecency database.<br><br><b><b>-l</b>, <b>--list</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;List all matched directories without changing the current working directory. The directories are ordered by frecency.<br><br><b><b>-r</b>, <b>--rank</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;List all directories in the database, sorted by frecency (highest frecency first).<br><br><b><b>-t</b>, <b>--recent</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;List all directories in the database, sorted by recency (most recently visited first).<br><br><b><b>-x</b>, <b>--exclude</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Exclude the current directory from being recorded in the database. Useful for temporary or sensitive directories.<br><br><b><b>-c</b>, <b>--cd</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Forces <i>z</i> to perform a <i>cd</i> operation even if it's typically aliased to another function (e.g., in some shell setups).<br><br><b><b>-e</b>, <b>--edit</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Opens the <i>z</i> database file in your default editor (specified by $EDITOR). Allows manual editing of directory frecency scores.<br><br><b><b>-h</b>, <b>--help</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Display a brief help message and exit.<br><br><b><b>-v</b>, <b>--version</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Display version information and exit.<br><br>


title: DESCRIPTION
content:
<i>z</i> is a popular command-line utility designed to make navigating frequently visited directories incredibly fast and efficient. Unlike traditional <i>cd</i> which requires precise paths, <i>z</i> learns your habits by keeping track of the directories you visit and how often you visit them. It then uses a <b>"frecency"</b> algorithm (a combination of frequency and recency) to rank these directories.<br><br>When you type <i>z</i> followed by a keyword, it attempts to find the best matching directory from its database and instantly changes your current working directory to it. This <b>fuzzy matching</b> capability saves significant time, especially for deeply nested or long directory names. It integrates seamlessly with your shell (Bash, Zsh, Fish) and is particularly useful for developers, system administrators, and anyone who frequently jumps between projects or system locations.


title: CAVEATS
content:
<i>z</i> is <b>not a standard Linux command</b>; it needs to be installed as a third-party utility. Its functionality relies on a database file, typically <i>~/.z</i>, which stores your directory visit history. If this file is corrupted or lost, <i>z</i> will lose its learned history. Performance might degrade slightly with an extremely large database, and fuzzy matching can occasionally lead to unexpected directory jumps if keywords are too generic.


title: INSTALLATION AND INTEGRATION
content:
<i>z</i> is typically installed by cloning its Git repository and then sourcing the <i>z.sh</i> script in your shell's configuration file (e.g., <i>~/.bashrc</i>, <i>~/.zshrc</i>). This integration ensures that every <i>cd</i> command is recorded by <i>z</i>.<br><br>Example:<br><i>git clone https://github.com/rupa/z.git ~/z<br>echo '. ~/z/z.sh' >> ~/.bashrc</i>


title: FRECENCY CALCULATION
content:
The 'frecency' score for a directory is a weighted combination of its frequency (how many times it's been visited) and its recency (how recently it was visited). <i>z</i> gives more weight to recent visits, making directories you've accessed recently rank higher, while also factoring in overall visit count. This dynamic scoring helps <i>z</i> adapt to your evolving navigation habits.


title: HISTORY
content:
The <i>z</i> command was created by <i>rupa</i> and first released around 2011. It was inspired by existing directory jump tools like <i>autojump</i> but aimed for a simpler, more lightweight implementation, focusing purely on the "frecency" algorithm. Written as a shell script, its portability and minimal overhead quickly led to its widespread adoption within the command-line user community as an efficient alternative to traditional directory navigation.


title: PARAMETERS
content:
<b>-u<character_name></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Starts the game playing as the specified character name.<br><br><b>-s<num></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Restores a saved game identified by its numerical index.<br><br><b>-n</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Starts a brand new game, discarding any existing character save for the current user.<br><br><b>-d<mode></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Enables a debug mode. Specific modes include 'g' for a graphical dump, 'c' for cheats, or 'x' for extended debug information.<br><br><b>-o<options_file></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Loads game options from the specified configuration file instead of the default.<br><br><b>-- _display_</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the X display to use for the game's graphical output, common in X11 environments.<br><br>


title: DESCRIPTION
content:
Zangband is a complex single-player <i>roguelike</i> game, a significantly expanded variant of <i>Angband</i>. Rooted in the traditions of <i>Umoria</i> and <i>Rogue</i>, the game challenges players to delve through a sprawling 100-level dungeon. The ultimate goal is to defeat the powerful monster residing on the deepest level and return victorious to the surface town. <br><br>Zangband distinguishes itself with a vast array of monsters, items, spells, and intricate character classes and races. It notably incorporates elements from Roger Zelazny's <b>Amber Chronicles</b>, introducing unique game mechanics such as Shadow Shifting and Pattern Walking. This integration enriches the gameplay with diverse strategic options and a deeper narrative context. The game emphasizes persistent world elements, profound character development, and strategic combat encounters, making it a highly configurable and engaging experience for fans of the genre.


title: CAVEATS
content:
Zangband is primarily a text-based (or tile-based with graphical frontends) game, requiring a terminal or X11 environment to run. Its gameplay can be extremely challenging and unforgiving, characteristic of the <i>roguelike</i> genre, with permanent character death. Compatibility with modern systems might vary, and some graphical modes or features may require specific library dependencies. Users might need to compile from source on certain distributions or use older package versions.


title: GAMEPLAY MECHANICS
content:
Zangband features a persistent town for resupplying and character management, and procedural generation for its dungeon levels, ensuring unique playthroughs. It includes a complex magic system, various combat styles, and a detailed inventory system with identification mechanics.


title: CHARACTER CUSTOMIZATION
content:
Players can choose from a wide array of races (including unique Amberite, Chaos Warrior, and various elemental types) and classes (such as Warrior, Mage, Priest, Rogue, and hybrid archetypes), each with distinct abilities, skill trees, and progression paths, leading to immense replayability.


title: HISTORY
content:
<i>Zangband</i> emerged as a major variant of <i>Angband</i>, itself a derivative of <i>Moria</i> and <i>Rogue</i>. Its development, notably led by Robert R. K. LeGrow, began to diverge significantly from the core <i>Angband</i> codebase in the mid-1990s. The name 'Zangband' specifically refers to the incorporation of elements from Roger Zelazny's acclaimed fantasy series, the <b>Amber Chronicles</b>, which introduced unique lore, races, classes, and mechanics like 'Pattern Walking' and 'Shadow Shifting'. This integration gave Zangband a distinct identity and significantly expanded the game's complexity and world-building beyond standard <i>Angband</i>. While development has slowed compared to its peak, it remains a beloved and influential branch in the roguelike family tree, known for its vast content and deep strategic possibilities.


title: SYNOPSIS
content:
<b>zapier</b> <i>&lt;command&gt;</i> [<i>options</i>]<br><b>zapier</b> init<br><b>zapier</b> login<br><b>zapier</b> push<br><b>zapier</b> deploy<br><b>zapier</b> help [<i>command</i>]


title: PARAMETERS
content:
<b>login</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Authenticates the CLI with your Zapier developer account, typically via an OAuth flow.<br><br><b>init</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Initializes a new Zapier app project in the current directory, setting up the basic file structure.<br><br><b>push</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Uploads the local app definition and code to Zapier for testing on the platform. This creates a private version of your app.<br><br><b>deploy</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Deploys a new, public version of your Zapier app to the platform, making it available for users.<br><br><b>test</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Runs local unit and integration tests against your app's code to ensure functionality.<br><br><b>validate</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Checks your app's definition for common errors and adherence to Zapier's platform guidelines.<br><br><b>logs</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Streams runtime logs from your deployed app on Zapier for debugging purposes.<br><br><b>env</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Manages environment variables for your Zapier app, useful for sensitive data or configuration.<br><br><b>shell</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Opens an interactive shell environment for direct testing and debugging of app actions and triggers.<br><br><b>--version, -v</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays the installed version of the Zapier CLI.<br><br><b>--help, -h</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays help information for the main command or a specific subcommand.<br><br>


title: DESCRIPTION
content:
The <b>zapier</b> command-line interface (CLI) is a powerful tool designed for developers to interact with the Zapier platform. Zapier itself is a web-based service that allows end-users to automate workflows by connecting different web applications without writing code. The <b>zapier</b> CLI extends this capability to developers, enabling them to build, test, and deploy custom integrations (known as 'Apps' or 'Connectors') directly from their development environment.<br><br>This allows for more complex, tailored automation scenarios that might not be possible with Zapier's visual interface alone. Developers use the CLI to initialize new projects, manage authentication, push updates, test app functionality, and deploy new versions of their integrations to the Zapier platform. It streamlines the development lifecycle for custom Zapier integrations, making it an essential tool for extending Zapier's capabilities.


title: CAVEATS
content:
The <b>zapier</b> command is not a standard Linux utility; it must be installed separately, typically via a Node.js package manager like <i>npm</i> or <i>yarn</i>. It requires an active internet connection and a Zapier developer account for most of its functionalities, as it interacts directly with Zapier's cloud platform. Its primary use case is for developers building custom integrations, not for general Zapier end-users.


title: AUTHENTICATION
content:
The <b>zapier</b> CLI requires authentication with a Zapier developer account. This is typically done using the <b>zapier login</b> command, which guides the user through an OAuth flow to link their local CLI session to their Zapier account. This authentication is crucial for pushing, deploying, and managing apps on the Zapier platform.


title: APP DEVELOPMENT WORKFLOW
content:
A typical development workflow using the <b>zapier</b> CLI involves initializing a new project (<b>zapier init</b>), developing app functionality locally, iteratively testing changes (<b>zapier test</b>), pushing updates to a private test version on Zapier (<b>zapier push</b>), and finally deploying (<b>zapier deploy</b>) a stable version for wider use on the Zapier platform.


title: HISTORY
content:
The Zapier CLI, often referred to as <i>zapier-platform-cli</i>, was developed by Zapier to provide a robust command-line interface for their Zapier Platform. Its development closely parallels the evolution of Zapier's developer platform, which allows third-party developers to extend Zapier's automation capabilities by creating custom apps. It was introduced to facilitate a more streamlined and programmatic approach to building, testing, and deploying these integrations, moving beyond just visual configuration. Its ongoing development reflects Zapier's commitment to empowering developers within its ecosystem.


title: SYNOPSIS
content:
<b>zapier-analytics</b> [<i>options</i>] <i>command</i> [<i>arguments</i>]<br><b>zapier-analytics</b> --help<br><b>zapier-analytics</b> --version<br><b>zapier-analytics</b> <i>report</i> [<i>--metric</i> <<i>name</i>>] [<i>--start-date</i> <<i>date</i>>] [<i>--end-date</i> <<i>date</i>>] [<i>--format</i> <<i>type</i>>]<br><b>zapier-analytics</b> <i>export</i> [<i>--metric</i> <<i>name</i>>] [<i>--output</i> <<i>file</i>>] [<i>--format</i> <<i>type</i>>]


title: PARAMETERS
content:
<b>--help, -h</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Display a help message and exit.<br><br><b>--version, -V</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Show program's version number and exit.<br><br><b>report</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Subcommand to generate analytical reports based on specified criteria.<br><br><b>export</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Subcommand to export raw or processed analytical data to a file.<br><br><b>--metric <name></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the analytics metric to query, e.g., &quot;task_runs&quot;, &quot;error_rate&quot;, &quot;api_calls&quot;.<br><br><b>--start-date <date></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Defines the beginning of the data collection period (e.g., YYYY-MM-DD).<br><br><b>--end-date <date></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Defines the end of the data collection period (e.g., YYYY-MM-DD).<br><br><b>--format <type></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the output format for data, such as &quot;json&quot;, &quot;csv&quot;, or &quot;table&quot;.<br><br><b>--output <file></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the file path to save exported data.<br><br><b>--user-id <id></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Filters analytics data to a specific Zapier user ID.<br><br><b>--workflow-id <id></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Filters analytics data to a specific Zap or workflow ID.<br><br><b>--period <type></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Aggregates data by a specific time period, e.g., &quot;daily&quot;, &quot;weekly&quot;, &quot;monthly&quot;.<br><br>


title: DESCRIPTION
content:
The <b>zapier-analytics</b> command is conceptualized as a specialized command-line interface (CLI) tool designed for interacting with Zapier's analytics infrastructure. It is not a standard Linux utility found in typical distributions but would likely be an internal tool or a specific CLI provided by Zapier for advanced users, developers, or internal operations. <br><br>Its primary purpose would be to extract, analyze, and present data related to Zapier automation usage, such as task run counts, error rates, workflow performance, and user activity. This tool could enable users to gain deeper insights into their Zapier integrations, monitor efficiency, identify bottlenecks, and make data-driven decisions regarding their automation strategies. It might support various data filtering, aggregation, and output formats to cater to different analytical needs, making complex Zapier usage data accessible directly from the command line.


title: CAVEATS
content:
It is important to note that <b>zapier-analytics</b> is <i>not a standard command-line utility available in typical Linux distributions</i>. This analysis is based on a hypothetical interpretation of what such a command would entail given its name and the nature of Zapier's services. If this command exists, it is likely an internal tool used by Zapier staff or a specialized CLI provided to specific partners or customers. Its actual functionality, parameters, and usage would depend entirely on its specific implementation by Zapier. Users should not expect to find this command pre-installed on their systems.


title: AUTHENTICATION
content:
Access to <b>zapier-analytics</b> would almost certainly require proper authentication against Zapier's API. This might involve API keys, OAuth tokens, or other secure credentials, potentially managed via environment variables or a configuration file.


title: DATA SCOPE
content:
The scope of data accessible via this command would likely be determined by the user's permissions and the specific Zapier account or workspace context. It might cover usage data, integration performance, error logs, and task execution details relevant to the authenticated user.


title: HISTORY
content:
As <b>zapier-analytics</b> is a hypothetical command, its history is purely speculative. If such a tool exists, it would likely have evolved internally within Zapier to meet the growing demands for data insights into their platform's usage and performance. Its development would align with Zapier's expansion and the increasing complexity of user workflows, requiring robust analytical capabilities to monitor system health, user engagement, and billing metrics. Its usage would primarily be internal for support, engineering, and business intelligence teams, or potentially released as a premium feature for enterprise clients needing detailed operational insights.


title: PARAMETERS
content:
<b><i>app_path</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Optional. Specifies the path to the root directory of the Zapier app project. If omitted, the command defaults to the current working directory.<br><br><b><i>--clean</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;When this option is used, the command will first remove the existing build output directory (typically <i>.zapierapp</i>) before creating a new build. This ensures a fresh build and helps prevent stale or cached files from being included.<br><br><b><i>--watch</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;This option enables 'watch mode'. In watch mode, the command continuously monitors the project files for changes. Upon detecting a change, it automatically triggers a rebuild of the app, which is particularly useful for rapid development and testing cycles.<br><br><b><i>--help</i>, <i>-h</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays a help message for the <b>zapier-build</b> command, detailing its usage, available options, and arguments.<br><br>


title: DESCRIPTION
content:
The <b>zapier-build</b> command is a utility within the Zapier Platform CLI designed to compile the source code of a custom Zapier integration app into a deployable bundle. It processes the JavaScript or TypeScript files, resolves dependencies, and optimizes the code, typically minifying it, to create a production-ready package. This built output, usually placed in a <i>.zapierapp</i> directory, is then ready to be pushed or deployed to the Zapier platform using commands like <b>zapier push</b> or <b>zapier deploy</b>. It plays a crucial role in the development workflow of Zapier apps, transforming human-readable code into an efficient format for the Zapier runtime environment.<br><br>While often invoked as a subcommand of the main <b>zapier</b> executable (i.e., <b>zapier build</b>), the prompt refers to <b>zapier-build</b>, which can be directly invoked if the CLI is installed globally or from the <i>node_modules/.bin</i> directory.


title: CAVEATS
content:
The <b>zapier-build</b> command is not a standard Linux utility; it is specific to the Zapier Platform CLI and requires <b>Node.js</b> to be installed on the system. It assumes a specific project structure for Zapier integration apps. Direct invocation as <b>zapier-build</b> might depend on how the Zapier CLI is installed (globally or locally) and the system's PATH configuration. Developers commonly use <b>zapier build</b> as part of the overall <b>zapier</b> CLI.


title: PREREQUISITES
content:
To use <b>zapier-build</b>, you must have <b>Node.js</b> installed on your system, and the <b>Zapier Platform CLI</b> (<i>zapier-platform-cli</i> npm package) must be installed globally or locally within your project.


title: BUILD OUTPUT
content:
Upon successful execution, <b>zapier-build</b> generates a new directory, typically named <i>.zapierapp</i> (configurable), within your project's root. This directory contains the compiled, minified, and optimized JavaScript bundle of your Zapier app, along with any necessary asset files and metadata. This packaged output is what Zapier reads when you publish or deploy your integration.


title: HISTORY
content:
The Zapier Platform CLI was introduced to empower developers to build custom integrations programmatically, offering more flexibility and power than the web-based builder alone. The <b>build</b> command has been a foundational component of this CLI since its early versions, providing the essential step to compile JavaScript or TypeScript source code into the bundled format required for the Zapier platform. Its functionality has remained consistent, focusing on packaging and optimizing app code for efficient execution within Zapier's environment.


title: SYNOPSIS
content:
As <b><code>zapier-convert</code></b> is not a standard Linux command, a universal synopsis does not exist. However, a hypothetical syntax for a data conversion utility based on its name might be:<br><br><code><b>zapier-convert</b> <i>[options]</i> <i>&lt;input_source&gt;</i> <i>&lt;output_destination&gt;</i></code><br><br>Where <i><code>options</code></i> would control conversion parameters, <i><code>&lt;input_source&gt;</i></code> specifies the source data (e.g., file path, URL, or standard input), and <i><code>&lt;output_destination&gt;</i></code> specifies where the converted data should go (e.g., file path, standard output).


title: PARAMETERS
content:
<b>(No standard parameters exist)</b><br>&nbsp;&nbsp;&nbsp;&nbsp;As <b><code>zapier-convert</code></b> is not a standard Linux command, there are no universally defined parameters. Any options would be specific to its custom implementation.<br><br>Hypothetical parameters for a typical data conversion tool might include:<br><ul><li><code>-f, --from &lt;format&gt;</code>: Specify the input data format (e.g., <code>csv</code>, <code>json</code>, <code>xml</code>).</li><li><code>-t, --to &lt;format&gt;</code>: Specify the desired output data format.</li><li><code>-i, --input &lt;path&gt;</code>: Path to the input file, or <code>-</code> for stdin.</li><li><code>-o, --output &lt;path&gt;</code>: Path for the output file, or <code>-</code> for stdout.</li><li><code>--encoding &lt;charset&gt;</code>: Specify character encoding for input/output.</li><li><code>--map &lt;rule&gt;</code>: Define rules for mapping or transforming fields.</li><li><code>--pretty-print</code>: Format output for human readability.</li></ul><br><br>


title: DESCRIPTION
content:
The command <b><code>zapier-convert</code></b> is not a standard, pre-installed Linux command. It is highly likely a custom script or application, possibly developed for specific data conversion tasks within or for integration with <a href='https://zapier.com' target='_blank'>Zapier</a> automation workflows.<br><br>If it were a real command, its primary function would be to transform data from one format to another (e.g., CSV to JSON, XML to YAML), making it compatible for different systems or stages within an automation pipeline. Its behavior, options, and exact capabilities would depend entirely on its specific implementation by the developer, designed to streamline data preparation for Zapier integrations or other automated processes.


title: CAVEATS
content:
The primary caveat is that <b><code>zapier-convert</code></b> is not a standard or commonly distributed Linux command. Its existence, functionality, and usage are entirely dependent on a specific, custom implementation by an individual or organization. Users will not find a man page for this command in typical Linux distributions, nor can its behavior be predicted without access to its source code or documentation from its developer.


title: CUSTOM IMPLEMENTATION
content:
This command likely exists as a private script or application tailored for specific data processing needs. It could be written in various scripting languages such as Python, Node.js, or even shell scripts, and deployed in environments that interact heavily with Zapier APIs or manipulate data streams before or after Zapier actions.


title: HISTORY
content:
As <b><code>zapier-convert</code></b> is not a standard Linux command, it does not have a documented public history of development or usage. Any history would be internal to the project or organization that created it for their specific needs, likely evolving with the requirements of their Zapier integrations or data pipelines.


title: SEE ALSO
content:
No directly related standard Linux commands due to its hypothetical and custom nature. Similar functionalities might be found in:, jq(1) - Lightweight and flexible command-line JSON processor., xsltproc(1) - Command-line XSLT processor for XML transformations., csvkit(1) - A suite of command-line tools for converting to and working with CSV., Python scripts - Often used for custom data conversion due to rich libraries (e.g., <code>pandas</code>, <code>json</code>, <code>csv</code>, <code>xml</code> modules).


title: PARAMETERS
content:
<b><i>&lt;project-name&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;The name of the directory to create for the new integration project. If omitted, the command will interactively prompt the user to provide a name.<br><br><b><b>--template</b> <i>&lt;template-name&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies a starting template for the project. Common template names include <i>trigger</i> (for a simple trigger app), <i>action</i> (for a simple action app), <i>search</i>, or <i>full</i> (for a comprehensive project structure).<br><br><b><b>--public</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Initializes the project with configurations typically required for a public Zapier integration, which may involve additional setup steps or default file structures suitable for submission to Zapier's App Directory.<br><br><b><b>--private</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Initializes the project as a private Zapier integration. This is the default behavior if neither <b>--public</b> nor <b>--private</b> is specified, suitable for internal tools or integrations not intended for public listing.<br><br><b><b>--debug</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Enables verbose output, displaying detailed information about the command's execution process, which can be useful for troubleshooting.<br><br><b><b>--help</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays a concise help message and usage information for the <b>zapier init</b> command.<br><br>


title: DESCRIPTION
content:
<i><b>zapier-init</b></i> is a command-line utility provided as part of the Zapier CLI, designed to streamline the process of starting new Zapier integration projects. When executed, it creates a new project directory with a pre-configured boilerplate, including essential files and directory structures necessary for developing a custom Zapier integration. This typically includes a <i>package.json</i> file, a <i>src</i> directory for code, and initial configuration files. It prompts the user for basic project details, such as the project name and type, ensuring that the scaffolding is tailored to the specific integration being built. By automating the setup process, <i><b>zapier-init</b></i> helps developers quickly get started, enforce best practices, and maintain consistency across different integration projects, saving time and reducing the chances of errors during initial setup. It's a crucial first step for anyone building a private or public Zapier app, offering a solid foundation to build upon.


title: CAVEATS
content:
Users must have Node.js and npm installed to use the Zapier CLI. The <b>zapier-platform-cli</b> package must be installed globally via npm before <b>zapier init</b> can be executed. While <b>zapier init</b> provides a solid boilerplate, successful integration development requires familiarity with JavaScript/Node.js and Zapier's platform concepts and best practices.


title: INSTALLATION
content:
The <b>zapier-init</b> command is a subcommand of the Zapier CLI, not a standalone utility. To make it available, you must first install the Zapier CLI globally using npm:<br><br><code>npm install -g zapier-platform-cli</code><br><br>Ensure you have Node.js and npm installed on your system before attempting this installation.


title: PROJECT STRUCTURE
content:
Upon successful execution, <b>zapier init</b> creates a new directory (named after your project) containing a structured boilerplate. This typically includes:<br>1. A <i>package.json</i> file for project metadata and dependencies.<br>2. A <i>src/</i> directory, which houses your integration's core logic (e.g., <i>index.js</i>).<br>3. Potentially other configuration files or subdirectories depending on the chosen <b>--template</b> or options, providing a ready-to-develop environment.


title: HISTORY
content:
The <b>zapier-init</b> command is an integral part of the Zapier CLI, which was introduced to empower developers to build and manage Zapier integrations more efficiently from their local development environments. Prior to the CLI, app development often involved more manual setup. The CLI, including <b>zapier-init</b>, streamlined the initial scaffolding and subsequent deployment processes, making it easier to manage versions and test integrations locally. Its evolution reflects Zapier's commitment to providing robust developer tools for its expanding platform.


title: PARAMETERS
content:
<b><URL></b><br>&nbsp;&nbsp;&nbsp;&nbsp;The specific Zapier webhook URL to which data will be sent. This URL is unique to each Zapier 'Catch Hook' trigger.<br><br><b>[DATA]</b><br>&nbsp;&nbsp;&nbsp;&nbsp;The data payload to be sent. This can be a simple string, a JSON object, or form-encoded data, depending on the Zapier webhook configuration. Often passed as a raw string or via a file.<br><br><b>--method <METHOD></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the HTTP method for the request, commonly <i>POST</i> for sending data to webhooks. Other methods like <i>GET</i>, <i>PUT</i>, or <i>DELETE</i> might be supported for more advanced API interactions.<br><br><b>--header <HEADER></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Adds a custom HTTP header to the request. Useful for setting content types (e.g., 'Content-Type: application/json') or authentication tokens.<br><br><b>--data-raw <DATA></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sends the specified data exactly as provided, often used for raw JSON or XML payloads.<br><br><b>--data-urlencode <KEY=VALUE></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sends data as URL-encoded form data. Multiple instances can be used for multiple key-value pairs.<br><br><b>--json <JSON_STRING></b><br>&nbsp;&nbsp;&nbsp;&nbsp;A convenience option to send data as JSON, automatically setting the 'Content-Type' header to 'application/json'.<br><br><b>--file <FILE></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Reads the data payload from a specified file. This is useful for sending large or complex data structures.<br><br><b>--verbose</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Enables verbose output, showing detailed information about the HTTP request and response, useful for debugging.<br><br>


title: DESCRIPTION
content:
The <b>zapier-push</b> command is a conceptual or custom utility, not a standard part of the Zapier CLI or typical Linux distributions. Its purpose is to facilitate the direct sending of data or events from a Linux command-line environment or script to a Zapier workflow (Zap). <br><br>Functionally, <b>zapier-push</b> would typically act as a wrapper around an HTTP client like <i>curl</i> or <i>wget</i>, simplifying the process of making HTTP POST requests to a Zapier webhook URL. Users often employ such a command to trigger Zaps from cron jobs, shell scripts, or interactive sessions, enabling automation tasks like logging events, triggering notifications, or initiating data processing workflows based on command-line operations. <br><br>While not officially distributed, the concept of <b>zapier-push</b> is highly practical for integrating custom scripts and server-side processes with Zapier's automation capabilities, bridging the gap between local system events and cloud-based workflows. It abstracts away the complexities of HTTP requests, making it easier to send structured data (e.g., JSON) to pre-configured Zapier webhooks.


title: CAVEATS
content:
<b>zapier-push</b> is generally a conceptual command or a user-created shell script/alias, not an official Zapier utility distributed with the Zapier CLI. Users must implement its functionality, typically by wrapping <i>curl</i> or similar HTTP clients. <br><br>Security is paramount; avoid hardcoding sensitive information (like API keys) directly in scripts. Use environment variables or secure configuration management. <br><br>Error handling is critical for production use. Custom scripts should check HTTP response codes and handle network issues gracefully.


title: TYPICAL IMPLEMENTATION
content:
A common way to implement <b>zapier-push</b> involves a shell script utilizing <i>curl</i>. For example, to send JSON data: <br><code>#!/bin/bash<br>URL="$1"<br>DATA="$2"<br>curl -X POST -H "Content-Type: application/json" -d "$DATA" "$URL"</code><br>This script could then be invoked as <code>zapier-push https://hooks.zapier.com/hooks/catch/... '{"event":"data_sent","value":123}'</code>.


title: ZAPIER WEBHOOK URLS
content:
Zapier webhook URLs (e.g., <code>https://hooks.zapier.com/hooks/catch/&lt;user_id&gt;/&lt;hook_id&gt;/</code>) are generated when you set up a 'Catch Hook' trigger in a Zapier workflow. They act as unique endpoints where external systems can send data to initiate the Zap.


title: HISTORY
content:
The concept behind <b>zapier-push</b> emerged with the rise of automation platforms like Zapier (and IFTTT). As these services gained popularity for connecting web applications, the need arose to trigger their workflows from traditional command-line environments and server-side scripts. Initially, users would manually craft complex <i>curl</i> commands. Over time, the convenience of wrapping these commands into simpler, custom scripts or aliases became apparent, leading to the informal development of tools conceptually akin to <b>zapier-push</b>. This trend reflects the broader movement towards 'DevOps' and 'Infrastructure as Code,' where system events and data are programmatically piped into automation pipelines.


title: PARAMETERS
content:
<b><b>directory_name</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;The name of the directory where the new Zapier application project will be created. If omitted, the command defaults to creating the project in the current working directory.<br><br><b><b>--template <I>NAME</I></b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies a starting template for the project. Common options include <i>basic</i> (a minimal setup) or <i>full</i> (a more comprehensive example with various authentication types, triggers, and actions).<br><br><b><b>--skip-install</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Prevents the command from automatically running <i>npm install</i> (or <i>yarn install</i>) after scaffolding, which can be useful for faster setup or when managing dependencies manually.<br><br><b><b>--public</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Scaffolds the app as a public integration, intended for general availability and use on the Zapier platform.<br><br><b><b>--private</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Scaffolds the app as a private integration, typically used for internal tools or specific client needs. This is the default behavior if neither <b>--public</b> nor <b>--private</b> is specified.<br><br><b><b>--enable-testing</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Configures the project with a basic testing framework setup, including sample tests to guide test-driven development practices.<br><br><b><b>--version</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays the version of the <i>zapier-platform-cli</i> currently installed and being used.<br><br><b><b>--help</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays comprehensive help information for the <i>init</i> command, detailing its usage and available options.<br><br>


title: DESCRIPTION
content:
The "zapier-scaffold" functionality refers to the project initialization capabilities provided by the <b>zapier-platform-cli</b> tool, primarily through the <b><I>zapier init</I></b> command. This command is meticulously designed to rapidly set up the foundational structure for a new Zapier integration, significantly reducing development time by generating essential files and directories. It creates a boilerplate project with predefined sections for authentication, triggers, and actions, alongside crucial configuration files such as <i>package.json</i> and a <i>.zapierapprc</i> file. This structured approach ensures consistency and adherence to Zapier's development guidelines, allowing developers to concentrate on the specific logic of their integration rather than spending time on tedious project setup. The generated project acts as a robust starting point, often including examples and placeholders that guide developers on where to integrate their custom code for connecting to external APIs and defining unique integration behaviors.


title: CAVEATS
content:
The term "zapier-scaffold" is not a standalone executable command but rather describes the project initialization (scaffolding) functionality within the <b>zapier-platform-cli</b>, primarily accessed via the <b><I>zapier init</I></b> command. To utilize this functionality, the <b>zapier-platform-cli</b> must be installed globally on your system using npm or yarn. The generated project serves as a starting template; significant further development, including API integration, authentication setup, and logic implementation, is required to create a fully functional Zapier app. This tool strictly requires Node.js to be installed and properly configured on your system.


title: INSTALLATION
content:
To gain access to the scaffolding functionality, you must first install the <b>zapier-platform-cli</b> globally on your system using either npm or yarn:<br><b><I>npm install -g zapier-platform-cli</I></b><br>or<br><b><I>yarn global add zapier-platform-cli</I></b>


title: GENERATED PROJECT STRUCTURE
content:
The <b><I>zapier init</I></b> command typically generates a well-organized project structure designed for modularity and ease of development. This structure commonly includes:<br><b><I>index.js</I></b>: The main entry point for your Zapier app.<br><b><I>authentication.js</I></b>: Defines how your app authenticates with external services.<br><b><I>triggers/</I></b>: A dedicated directory for files defining new triggers (events your app can listen for and respond to).<br><b><I>actions/</I></b>: A dedicated directory for files defining new actions (tasks your app can perform in external services).<br><b><I>test/</I></b>: A directory intended for unit and integration tests.<br><b><I>package.json</I></b>: The Node.js project manifest file, listing dependencies and project metadata.<br><b><I>.zapierapprc</I></b>: A configuration file specific to the Zapier CLI.<br>This structured layout significantly promotes modularity, maintainability, and makes it considerably easier to manage complex integrations as your app evolves.


title: HISTORY
content:
The <b>zapier-platform-cli</b> was developed by Zapier to empower developers and streamline the creation and management of custom integrations for their platform. In its early stages, developers often had to manually set up project structures, a process that was both time-consuming and prone to errors. The pivotal introduction of scaffolding capabilities, most notably through the <b><I>zapier init</I></b> command, dramatically simplified this process by providing standardized, ready-to-use templates. This evolution underscores Zapier's unwavering commitment to enabling developers to rapidly build and deploy robust integrations, significantly lowering the barrier to entry for custom app development and fostering a more efficient ecosystem.


title: PARAMETERS
content:
<b><b>-P &lt;password&gt;</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specify the password for encrypted PDF documents. This allows opening password-protected files directly from the command line.<br><br><b><b>-c &lt;command&gt;</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Execute a Zathura command string immediately after startup. This can be used for automation, like jumping to a specific page or setting a view mode.<br><br><b><b>-e &lt;encoding&gt;</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Set the text encoding for text-based documents or when extracting text. Useful for documents with non-standard encodings.<br><br><b><b>-p &lt;page&gt;</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Open the document at a specific page number. Pages are 1-indexed.<br><br><b><b>-s</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Start Zathura in fullscreen mode. This maximizes the viewing area for the document.<br><br><b><b>-U &lt;uri&gt;</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Open a document from a Uniform Resource Identifier (URI), which can be a local file path or a URL for remote documents.<br><br><b><b>-v</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Display Zathura's version information and exit. Useful for checking the installed version and build details.<br><br>


title: DESCRIPTION
content:
Zathura is a highly customizable and functional document viewer for various formats, primarily known for its PDF capabilities. It is designed to be lightweight, fast, and keyboard-driven, drawing significant inspiration from the <I>Vim</I> editor for its navigation and command-line interface. Zathura's minimalistic interface focuses solely on the document content, reducing visual clutter and enhancing readability. <br><br>Its extensible architecture relies on a plugin system, allowing it to support different document types such as PDF, PostScript, DjVu, Comic Book Archives (CBZ/CBR), and more, depending on the installed plugins. This design makes the core application very lean. Zathura is particularly popular among users who prefer keyboard-centric workflows and seek a highly configurable and efficient document viewing experience on Linux and other Unix-like systems.


title: CAVEATS
content:
Zathura's ability to open specific document formats is entirely dependent on the availability and installation of its corresponding plugins (e.g., <B>zathura-pdf-poppler</B> for PDFs, <B>zathura-ps</B> for PostScript, <B>zathura-djvu</B> for DjVu). Without the necessary plugin, Zathura will not be able to render the file type. Users new to Zathura might also find its keyboard-driven, modal interface to have a steeper learning curve compared to traditional mouse-centric document viewers.


title: CONFIGURATION FILES
content:
Zathura is extensively configurable through its configuration file, typically located at <I>~/.config/zathura/zathurarc</I>. Users can customize virtually every aspect, including keybindings, colors, font settings, and behavior. This file uses a simple syntax, allowing for powerful personalization.


title: KEYBINDINGS
content:
The command features a rich set of default keybindings, heavily inspired by <I>Vim</I>. Users can navigate, search, zoom, rotate, and perform many other actions using only the keyboard. These keybindings are fully customizable within the <I>zathurarc</I> file.


title: PLUGIN SYSTEM
content:
Zathura's modular design means that support for different document formats is provided by separate plugins. This keeps the core application small and efficient. Common plugins include <B>zathura-pdf-poppler</B> (for PDF), <B>zathura-djvu</B> (for DjVu), <B>zathura-ps</B> (for PostScript), and <B>zathura-cb</B> (for comic book archives).


title: HISTORY
content:
Zathura was developed by Simon Schmeisser and other contributors as a lightweight and highly configurable document viewer, first released around 2009. Its design philosophy emphasizes speed, minimalism, and keyboard control, distinguishing it from more feature-rich, mouse-driven alternatives. It draws significant inspiration from projects like the Vim text editor and the Suckless tools (e.g., <I>surf</I>, <I>dwm</I>) in its approach to simplicity and user control through configuration files and keybindings.


title: PARAMETERS
content:
<b><b>-h</b>, <b>--help</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays a concise help message with available command-line options and usage information.<br><br><b><b>-V</b>, <b>--version</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Prints the version information of the <b>zbarcam</b> utility and the underlying ZBar library.<br><br><b><b>-v</b>, <b>--verbose</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Enables verbose output, providing more detailed information about the scanning process, detected symbols, and any errors encountered.<br><br><b><b>-q</b>, <b>--quiet</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Suppresses all verbose messages, ensuring only decoded barcode data is printed to standard output.<br><br><b><b>-s</b><i>&lt;config&gt;</i>, <b>--set</b> <i>&lt;config&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Configures specific options for a barcode symbology. The <i>&lt;config&gt;</i> format is <i>[symbology.]config[=value]</i>, where <i>symbology</i> can be EAN13, QR-Code, Code128, etc., and <i>config</i> specifies options like <i>enable</i>, <i>disable</i>, <i>min-len</i>, <i>max-len</i>, <i>position</i>.<br><br><b><b>--raw</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Outputs only the raw symbol data (the decoded barcode content) to standard output, without the symbol type prefix.<br><br><b><b>--xml</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Outputs the decoded barcode information in XML format, providing structured data including symbol type, data, and optional position information.<br><br><b><b>--</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Marks the end of command-line options, allowing the specification of a video device path that might start with a hyphen (e.g., <i>-- -mydevice</i>).<br><br><b>[<i>device</i>]</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the video input device to use. If omitted, <b>zbarcam</b> defaults to <i>/dev/video0</i>. Other common devices include <i>/dev/video1</i>, etc.<br><br>


title: DESCRIPTION
content:
The <b>zbarcam</b> command is a powerful utility from the ZBar barcode reader library, designed to capture and decode barcodes directly from a video input device, such as a webcam. It provides real-time barcode scanning capabilities, making it ideal for applications requiring immediate data extraction from physical barcodes. <br><br>Utilizing the Video4Linux (V4L) API, <b>zbarcam</b> can access and process video frames from `/dev/video` devices. It supports a wide range of popular 1D and 2D barcode symbologies, including EAN, UPC, Code128, and QR codes. Once a barcode is detected and decoded, <b>zbarcam</b> outputs the symbol type and its decoded data to standard output, making it easily scriptable or integratable into other systems. It's a command-line tool, providing a lean and efficient way to perform live barcode recognition without a graphical interface.


title: CAVEATS
content:
<b>zbarcam</b> requires a compatible video input device (e.g., webcam) that is supported by the Linux V4L (Video4Linux) subsystem. Performance and accuracy are highly dependent on the camera's resolution, lighting conditions, and the clarity of the barcode. It does not provide a graphical user interface, operating purely on the command line. Users may need to install additional kernel modules or packages (like `v4l-utils`) for full camera functionality.


title: DEFAULT OUTPUT FORMAT
content:
By default, <b>zbarcam</b> outputs each decoded barcode on a new line, prefixed by its symbology type. For example: <i>EAN13:1234567890123</i> or <i>QR-Code:Hello World</i>.


title: SUPPORTED SYMBOLOGIES
content:
<b>zbarcam</b> supports a wide array of barcode types, including but not limited to: <i>EAN-13</i>, <i>EAN-8</i>, <i>UPC-A</i>, <i>UPC-E</i>, <i>ISBN-10</i>, <i>ISBN-13</i>, <i>Interleaved 2 of 5 (I2/5)</i>, <i>Code 39</i>, <i>Code 93</i>, <i>Code 128</i>, <i>Codabar</i>, and <i>QR Code</i>. Specific symbologies can be enabled or disabled using the <b>--set</b> option.


title: SELECTING VIDEO DEVICE
content:
The target video device can be explicitly specified as the last argument, e.g., <i>zbarcam /dev/video1</i>. If no device is specified, <b>zbarcam</b> defaults to <i>/dev/video0</i>. Ensure the user running <b>zbarcam</b> has read access to the specified device file.


title: HISTORY
content:
<b>zbarcam</b> is an integral part of the ZBar Barcode Reader project, an open-source software suite developed to read barcodes from various sources, including image files and video streams. The project was initiated to provide a robust and flexible barcode scanning solution for a wide range of 1D and 2D symbologies. Since its inception, ZBar and its utilities like <b>zbarcam</b> have been adopted by developers for applications requiring efficient, real-time barcode decoding in Linux and other Unix-like environments, leveraging the system's video capabilities.


title: PARAMETERS
content:
<b>-h, --help</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Show help message and exit.<br><br><b>-V, --version</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Display version information and exit.<br><br><b>-q, --quiet</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Suppress informational messages; only print barcode data.<br><br><b>-v, --verbose</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Enable verbose debugging output for diagnostics.<br><br><b>-d, --display</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Display decoded images in a window (requires X11/GTK+ support).<br><br><b>-o <file>, --output=<file></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Write modified output image (e.g., with detected barcodes highlighted) to the specified file.<br><br><b>-r, --raw</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Print raw decoded data (bytes) for each barcode, without interpretation.<br><br><b>-x, --xml</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Print results in XML format, providing structured data about each barcode.<br><br><b>-S <symbol>[.<config>]=<value>, --set <symbol>[.<config>]=<value></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Configure the decoder for a specific symbol type. E.g., '<i>--set qr.enabled=1</i>' or '<i>--set *.disable</i>' to disable all decoders.<br><br><b>-P <preset>, --preset=<preset></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Apply a named configuration preset (e.g., <i>default</i>, <i>fast</i>, <i>dense</i>) for decoding.<br><br><b>-f <format>, --formats=<format></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Limit scanning to specific barcode formats, comma-separated (e.g., '<i>--formats=EAN-13,QR-Code</i>').<br><br><b>-s <size>, --max-size=<size></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Set the maximum image size for processing (e.g., '<i>640x480</i>'). Images larger than this may be scaled down.<br><br><b>-s <scale>, --scale=<scale></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Scale the image before scanning (e.g., '<i>0.5</i>' for half size, '<i>2</i>' for double size).<br><br><b>-t, --time</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Print decode time statistics for performance analysis.<br><br>


title: DESCRIPTION
content:
<b>zbarimg</b> is a command-line utility from the <i>ZBar bar code reader</i> project designed to scan and decode bar codes from image files. It supports a variety of common 1D and 2D bar code symbologies, including QR Code, Data Matrix, EAN-13, UPC-A, Code 39, Code 128, and more. Users can feed one or more image files as input, and <b>zbarimg</b> will attempt to locate and decode any bar codes present within them. The command offers flexibility in output format, allowing users to choose between human-readable text, raw data, or XML output. It's a valuable tool for automating barcode reading from images in scripting or batch processing scenarios, often used in conjunction with other image manipulation tools.


title: CAVEATS
content:
<b>zbarimg</b>'s performance can vary significantly based on image quality, resolution, barcode size, and background complexity.<br>For very large images or images with many barcodes, processing can be slow or consume significant memory.<br>Some barcode types or configurations might require specific <i>--set</i> options to be enabled for successful decoding.<br>The <i>--display</i> option requires X11/GTK+ support to be compiled into the <b>zbarimg</b> binary, which may not be present in all installations.


title: BARCODE SYMBOLOGY CONFIGURATION
content:
Users can fine-tune which barcode types <b>zbarimg</b> attempts to decode using the <i>--set</i> and <i>--formats</i> options. For example, to only look for QR Codes and EAN-13, you would use '<i>--formats=QR-Code,EAN-13</i>'. To disable a specific decoder (e.g., Code 39), use '<i>--set code39.disable=1</i>'. This helps improve performance by focusing the decoder on relevant symbologies and can prevent misreads from unintended barcode types.


title: IMAGE PREPROCESSING FOR BETTER RESULTS
content:
While <b>zbarimg</b> has internal image processing capabilities, feeding it well-prepared images can significantly improve decoding success rates, especially with challenging inputs. Cropping, deskewing, binarizing, or adjusting contrast in an external image editor (like <i>ImageMagick</i> or <i>GraphicsMagick</i>) before passing to <b>zbarimg</b> can be beneficial for images with poor lighting, low contrast, or complex backgrounds.


title: HISTORY
content:
The <i>ZBar bar code reader</i> project was initiated by <i>Jeff Brown</i>, with the goal of providing an open-source software suite for reading bar codes from various sources, including images and video streams. <b>zbarimg</b> is a fundamental component of this project, offering a simple yet powerful command-line interface for batch processing image files. Its development focuses on broad barcode symbology support and efficient decoding algorithms, making it a widely adopted tool in open-source barcode solutions.


title: PARAMETERS
content:
<b>-f, --force</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Force decompression, even if the file has multiple links, or the output file already exists and is not a terminal.<br><br><b>-h, --help</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Display a help message and exit.<br><br><b>-q, --quiet</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Suppress all warnings.<br><br><b>-V, --version</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Display the version number and exit.<br><br>


title: DESCRIPTION
content:
<b>zcat</b> is a Linux command-line utility used to decompress files compressed with the <i>gzip</i> algorithm and print their content to standard output. It functions identically to executing <i>gunzip -c</i> or <i>gzip -dc</i>. The primary advantage of <b>zcat</b> lies in its ability to quickly display the contents of a compressed file without requiring the user to store the decompressed version on disk, which is particularly useful for frequently accessed log files, configuration files, or data archives.<br><br>Because its output is directed to standard output, <b>zcat</b>'s power is amplified when combined with other commands via pipes. Users can easily pipe its output to viewers like <i>less</i>, search tools like <i>grep</i>, or text processing utilities such as <i>awk</i> and <i>sed</i>, enabling efficient on-the-fly analysis of compressed data. It automatically handles files with common <i>gzip</i> extensions like .gz, .taz, .tgz, or .z.


title: CAVEATS
content:
<b>zcat</b> is specifically designed for files compressed with <i>gzip</i>. It will not work for files compressed with other algorithms like <i>bzip2</i> (use <i>bzcat</i>) or <i>xz</i> (use <i>xzcat</i>). Its output is always directed to standard output; it does not create a decompressed file on disk.


title: PIPING OUTPUT
content:
The most common use case for <b>zcat</b> is piping its output to other commands for processing. For example, <code>zcat syslog.gz | grep ERROR</code> allows searching for patterns within a compressed log file without decompressing it to disk.


title: MULTIPLE FILES
content:
When multiple compressed files are provided as arguments, <b>zcat</b> concatenates their decompressed contents sequentially to standard output. For instance, <code>zcat log1.gz log2.gz > combined_logs.txt</code> will decompress and merge the two files.


title: HISTORY
content:
<b>zcat</b> emerged as part of the <i>gzip</i> project, initiated by Jean-loup Gailly in 1992 as a free, open-source replacement for the proprietary <i>compress</i> program. Its goal was to provide better compression ratios and avoid patent issues associated with the LZW algorithm. <b>zcat</b> was included as a convenient front-end, simplifying the common task of viewing compressed file contents directly, without explicit decompression and re-compression steps, solidifying its role as a fundamental utility in Unix-like operating systems.


title: PARAMETERS
content:
<b><i>cmp_options</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Any valid option supported by the underlying <i>cmp</i> command. <i>zcmp</i> passes these options directly to <i>cmp</i>. Common options include:<br><br><b>-l, --verbose</b><br>&nbsp;&nbsp;&nbsp;&nbsp;For each difference, print the byte number (decimal) and the differing byte values (octal) for both files.<br><br><b>-s, --quiet, --silent</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Suppress all output. Only the exit status indicates whether the files differ.<br><br><b>-n <i>BYTES</i>, --bytes=<i>BYTES</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Compare only the first <i>BYTES</i> bytes of the files.<br><br><b><i>file1</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;The path to the first file to compare. This file can be compressed (e.g., <i>file.txt.gz</i>) or uncompressed.<br><br><b><i>file2</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;The path to the second file to compare. This file can also be compressed or uncompressed. If <i>file2</i> is omitted, <i>zcmp</i> (and the underlying <i>cmp</i>) will generally return an error, as <i>cmp</i> requires two files for comparison.<br><br>


title: DESCRIPTION
content:
The <i>zcmp</i> command serves as a convenient wrapper around the standard <i>cmp</i> utility, specifically designed for comparing files that are compressed. It automatically decompresses the specified files on-the-fly using appropriate tools like <i>gzip</i>, <i>bzip2</i>, or <i>xz</i>, and then pipes their uncompressed content to <i>cmp</i> for byte-by-byte comparison.<br><br>This allows users to compare compressed archives without needing to manually decompress them first, simplifying workflows when dealing with large datasets or system backups. <i>zcmp</i> essentially extends the functionality of <i>cmp</i> to compressed data, providing the same comparison logic and output formats. It supports various common compression formats, allowing for seamless comparison regardless of the underlying compression method.


title: CAVEATS
content:
<b>Performance Overhead</b>: Decompressing files on-the-fly introduces a performance overhead compared to comparing uncompressed files directly. This can be significant for very large files or slow CPUs.<br><b>Temporary Files</b>: While modern implementations often stream content, older versions or specific configurations might create temporary uncompressed files, potentially consuming disk space and increasing I/O.<br><b>Error Handling</b>: Errors can originate from either the decompression utility (e.g., corrupted archive, unsupported format) or the <i>cmp</i> command itself (e.g., permission issues, non-existent files). <i>zcmp</i>'s error messages will reflect the source of the problem.<br><b>Limited Unique Options</b>: <i>zcmp</i> itself doesn't add many unique options beyond handling compressed input; its power comes from leveraging <i>cmp</i>'s options with compressed data.


title: EXIT STATUS
content:
<i>zcmp</i> returns an exit status indicating the comparison result, consistent with <i>cmp</i>:<br><b>0</b>: The files are identical.<br><b>1</b>: The files differ.<br><b>2</b>: An error occurred (e.g., inaccessible file, invalid arguments, decompression failure).


title: HISTORY
content:
The <i>zcmp</i> command is typically distributed as part of the <i>gzip</i> package or similar compression utilities on Linux and Unix-like systems. It emerged as a practical utility to streamline operations on compressed files, mirroring the existing <i>cmp</i> functionality without requiring manual decompression steps. Its development has focused on providing a transparent wrapper that intelligently handles various compression formats supported by the underlying system's decompression tools, making it a staple for system administrators and users working with compressed data.


title: PARAMETERS
content:
<b>-b</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Dump block information, including allocated and bad blocks.<br><br><b>-c</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Dump configuration information for the pool or vdev.<br><br><b>-d</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Dump specific data blocks. Can be used multiple times for increased verbosity (e.g., -ddd).<br><br><b>-D</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Dump DDT (Deduplication Table) statistics and information.<br><br><b>-e</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Suppress printing of empty entries in output.<br><br><b>-E</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Print errors encountered during the scan or dump.<br><br><b>-h</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Display the help message and exit.<br><br><b>-i</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Inspect vdev I/O statistics and block allocation.<br><br><b>-k</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Dump kernel-level ZFS statistics (on supported systems).<br><br><b>-L</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Look up a specific ZFS object by its ID.<br><br><b>-m</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Dump the contents of the MOS (Meta Object Set).<br><br><b>-o <object_id></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specify a specific object ID to inspect (often used with -L or -d).<br><br><b>-P</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Dump pathname information for objects.<br><br><b>-s</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Summarize space usage per block type within the pool.<br><br><b>-U</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Dump the unallocated space map.<br><br><b>-v</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Increase verbosity of output. Can be used with other flags.<br><br><b>-X <uberblock_id></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Examine a specific uberblock by its ID.<br><br>


title: DESCRIPTION
content:
<i>zdb</i> (ZFS Debugger) is a powerful, low-level diagnostic tool designed to examine the internal on-disk structure of a ZFS storage pool or dataset. Unlike <b>zpool</b> or <b>zfs</b> which provide high-level management and reporting, <i>zdb</i> delves into the raw metadata and data blocks, allowing administrators and developers to inspect block pointers, DDTs (deduplication tables), MOS (Meta Object Set), space maps, and other core components.<br><br>It's primarily used for deep-dive debugging, understanding ZFS internals, and in rare cases, aiding in data recovery or corruption analysis when standard tools are insufficient. Its output is highly verbose and requires a detailed understanding of ZFS architecture. It operates in a read-only mode, ensuring no modifications are made to the pool.


title: CAVEATS
content:
<i>zdb</i> requires deep knowledge of ZFS internals for effective use. Its output is extremely verbose and complex, making it unsuitable for casual or routine administration.<br><br>While it operates in a read-only mode, misinterpretation of its diagnostic output could lead to incorrect assumptions or recovery attempts if not handled by experienced users or ZFS experts.


title: COMMON USE CASES
content:
<i>Diagnosing Corruption</i>: When <b>zpool scrub</b> or <b>zpool status</b> report errors that are hard to diagnose, <i>zdb</i> can provide detailed insights into the corrupted blocks or metadata.<br><br><i>Understanding Space Usage</i>: Options like <b>zdb -s</b> and <b>zdb -U</b> help in understanding how space is allocated and what types of blocks consume space.<br><br><i>Deep Dive Debugging</i>: For ZFS developers or system administrators troubleshooting highly complex issues, <i>zdb</i> allows direct inspection of on-disk structures, crucial for understanding specific bugs or recovery scenarios.


title: OUTPUT INTERPRETATION
content:
The output of <i>zdb</i> is highly specialized and often involves hexadecimal addresses, block pointers, and internal ZFS object IDs.<br><br>Understanding requires familiarity with ZFS concepts like Data Management Units (DMU), ZIO pipeline, block pointers, copy-on-write, uberblocks, and the Meta Object Set (MOS).<br><br>It's often used in conjunction with ZFS source code or detailed architectural documentation for full comprehension.


title: HISTORY
content:
ZFS (Zettabyte File System) was originally developed by Sun Microsystems for Solaris, designed for large-scale data storage and integrity. <i>zdb</i> was an integral part of the ZFS suite from its early days, providing the necessary low-level introspection capabilities for development, debugging, and post-mortem analysis.<br><br>With the open-sourcing of ZFS (OpenZFS), <i>zdb</i> continued its role as a critical diagnostic utility, evolving alongside the filesystem itself to support new features and address complex data integrity issues across various platforms like Linux, FreeBSD, and macOS. Its design reflects the robust, self-healing, and diagnostic-friendly nature of ZFS.


title: SYNOPSIS
content:
<b>zdiff</b> [<i>diff_options</i>] <i>file1</i> [<i>file2</i>]<br><b>zdiff</b> [<i>diff_options</i>] <b>--</b> <i>file1</i> <i>file2</i>


title: PARAMETERS
content:
<b><i>diff_options</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Any option accepted by the standard <i>diff</i> command. <i>zdiff</i> passes these options directly. Examples include:<br><b>-u</b>: Output in unified context format.<br><b>-c</b>: Output in context format.<br><b>-N</b>: Treat absent files as empty.<br><b>-q</b>: Report only whether files differ, not the details.<br><b>-i</b>: Ignore changes in white space at line end.<br><br><b><i>file1</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;The path to the first compressed file to compare. If <i>file2</i> is omitted, <i>zdiff</i> compares <i>file1</i> with standard input.<br><br><b><i>file2</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;The path to the second compressed file to compare. If omitted, <i>file1</i> is compared with standard input.<br><br>


title: DESCRIPTION
content:
<i>zdiff</i> is a utility designed to compare the content of compressed files by transparently decompressing them on-the-fly and feeding their output to the standard <i>diff</i> command. It supports files compressed with common utilities like <i>gzip</i> (.gz), <i>compress</i> (.Z), <i>bzip2</i> (.bz2), <i>lzma</i> (.lzma), <i>xz</i> (.xz), and <i>zstd</i> (.zst, if available). By acting as a wrapper, <i>zdiff</i> eliminates the need for manual decompression before comparing files, streamlining workflows for users dealing with archived data. All options provided on the command line are directly passed to the underlying <i>diff</i> command, allowing users to leverage <i>diff</i>'s extensive comparison capabilities.


title: CAVEATS
content:
Requires the <i>diff</i> command to be installed and accessible in the system's PATH.<br>Appropriate decompression utilities (e.g., <i>gzip</i>, <i>bzip2</i>, <i>xz</i>, <i>zstd</i>) must be installed for <i>zdiff</i> to handle corresponding compressed file types.<br>On-the-fly decompression can introduce a performance overhead compared to comparing uncompressed files directly.<br>Memory usage might be higher as files are decompressed in memory or to temporary locations.


title: EXIT STATUS
content:
<i>zdiff</i> returns the exit status of the underlying <i>diff</i> command:<br><b>0</b>: No differences were found between the files.<br><b>1</b>: Differences were found.<br><b>2</b>: An error occurred (e.g., file not found, permission denied).


title: HISTORY
content:
<i>zdiff</i> is part of the <i>gzip</i> package, which was initially developed by Jean-loup Gailly and Mark Adler. It emerged as a practical wrapper for <i>diff</i>, addressing the growing need to compare large text files that were increasingly being stored in compressed formats to save disk space and expedite transfers. Its design as a simple front-end to <i>diff</i> allowed it to leverage <i>diff</i>'s robust comparison algorithms while transparently handling decompression, making it a staple utility in environments where compressed data is common.


title: SYNOPSIS
content:
<b>zdump</b> [<i>OPTION</i> ...] [<i>ZONENAME</i> ...] <br><b>zdump</b> [<i>OPTION</i> ...] <b>--input-file</b>=<i>FILE</i>


title: PARAMETERS
content:
<b><i>ZONENAME</i> ...</b><br>&nbsp;&nbsp;&nbsp;&nbsp;One or more time zone names (e.g., "America/New_York", "Europe/London") for which to display information. These names correspond to files within the system's time zone database.<br><br><b><b>-v</b>, <b>--verbose</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Dumps extensive time zone information, including the time at the lowest and highest possible values and all time transitions (e.g., daylight saving time changes) from 1970 up to the present and into the future.<br><br><b><b>-c</b> <i>YEAR</i>, <b>--until-year</b>=<i>YEAR</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Limits the dumped information to transitions occurring up to the specified year (inclusive). This helps to narrow down the output for verbose queries.<br><br><b><b>-t</b> <i>TIMESTAMP</i>, <b>--timestamp</b>=<i>TIMESTAMP</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Dumps information only at the given Unix epoch timestamp. This is useful for checking the time zone behavior at a specific point in time.<br><br><b><b>-i</b> <i>FILE</i>, <b>--input-file</b>=<i>FILE</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Reads a list of time zone names to process from the specified file, one name per line. This is convenient for processing multiple zones without listing them on the command line.<br><br><b><b>--version</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Outputs version information about <i>zdump</i> and exits.<br><br><b><b>--help</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays a help message with usage instructions and available options, then exits.<br><br>


title: DESCRIPTION
content:
<i>zdump</i> is a utility for displaying detailed time zone information. It can show the current time in specified time zones, along with crucial details like the time at the lowest and highest possible timestamp values, and all past and future time transitions. This is particularly useful for understanding how a time zone behaves over time, including changes due to daylight saving time (DST) or historical time zone rule alterations. It queries the system's time zone database (typically <i>/usr/share/zoneinfo</i>) to provide accurate and comprehensive output, making it an invaluable tool for system administrators and developers dealing with time-sensitive applications and data.


title: CAVEATS
content:
<i>zdump</i>'s accuracy is entirely dependent on the currency and integrity of the system's installed time zone database (typically the IANA Time Zone Database). If this database is outdated, the output for future or even past transitions may be incorrect. The verbose output (with <b>-v</b>) can be very extensive for time zones with numerous historical changes. Note that <i>zdump</i> does not perform time zone conversion itself; it reports on the properties and transitions of time zone definitions.


title: OUTPUT DETAILS
content:
When run without the <b>-v</b> (verbose) option, <i>zdump</i> typically shows the current time in the specified time zone. With <b>-v</b>, it outputs a detailed list of time transitions, including the Unix epoch timestamp, the local time before and after the transition, the corresponding time zone abbreviation, and the daylight saving time (DST) status. This verbose output is crucial for understanding historical and future time adjustments for a given zone.


title: TIME ZONE DATABASE
content:
<i>zdump</i> relies on the system's time zone information files, typically located under <i>/usr/share/zoneinfo</i>. These files constitute the IANA Time Zone Database (also known as the Olson database), which is a collaborative compilation of worldwide time zone changes and rules. Keeping this database up-to-date is essential for <i>zdump</i> to provide accurate and current information.


title: HISTORY
content:
<i>zdump</i> is an integral part of the <i>tzdata</i> (Time Zone Database) package, widely known as the IANA Time Zone Database or Olson database. It has been a standard utility for inspecting time zone data on Unix-like systems for decades. Its fundamental role has remained consistent: to provide a programmatic way to examine the behavior of defined time zones over historical and future periods, evolving alongside updates to the authoritative time zone data itself.


title: SYNOPSIS
content:
<b>zeek</b> [<i>options</i>] [<i><script_files></i>...]<br><i>Common usage:</i><br><b>zeek</b> <i>-r <pcap_file></i> [<i><script_files></i>...]<br><b>zeek</b> <i>-i <interface></i> [<i><script_files></i>...]


title: PARAMETERS
content:
<b><i>-r <file></i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Reads network traffic from the specified PCAP <i>file</i> instead of a live interface.<br><br><b><i>-i <interface></i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Reads network traffic live from the specified network <i>interface</i>.<br><br><b><i>-C</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Disables MD5 checksum verification for PCAP files during processing.<br><br><b><i>-N</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Disables checksum validation for TCP/IP traffic, useful for non-standard captures.<br><br><b><i>-p</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Prevents the network interface from being put into promiscuous mode.<br><br><b><i>-B <size></i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets the network buffer <i>size</i> in bytes for the capture interface.<br><br><b><i>-s <snapshot_len></i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets the snaplen (snapshot length) to capture only the first <i>snapshot_len</i> bytes of each packet.<br><br><b><i>-b <BPF_filter></i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Applies a Berkeley Packet Filter (BPF) <i>filter</i> to incoming network traffic.<br><br><b><i>-U</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Prevents Zeek from loading its default set of policy scripts.<br><br><b><i>-q</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Suppresses all warning messages during execution.<br><br><b><i>-v</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Prints the Zeek version information and exits.<br><br><b><i>-h</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays the command-line help message and exits.<br><br>


title: DESCRIPTION
content:
<b>Zeek</b>, formerly known as Bro, is an open-source, powerful network analysis framework designed for deep packet inspection and comprehensive security monitoring. Unlike traditional Intrusion Detection Systems (IDS), Zeek doesn't merely flag malicious activity; it produces a comprehensive, high-fidelity archive of network traffic for forensics, historical analysis, and threat hunting. It achieves this by dissecting network protocols, extracting application-layer content, and generating detailed, semantically-rich logs (e.g., connection logs, HTTP logs, DNS logs, file transfers, SSL certificates). Zeek's policy script language allows security analysts to define custom detection logic, perform advanced protocol analysis, and implement site-specific security policies. It is widely used in enterprise, government, and research environments for incident response, threat intelligence, and network performance monitoring.


title: CAVEATS
content:
<b>Zeek</b> can be resource-intensive (CPU, RAM, disk I/O) especially for high-volume network traffic. It requires significant configuration, understanding of its scripting language, and proper log management for optimal utilization. It functions as a powerful detection and logging system, rather than a preventative or blocking tool.


title: RICH LOGGING
content:
<b>Zeek</b> automatically generates a comprehensive set of highly detailed, structured logs (e.g., <i>conn.log</i>, <i>http.log</i>, <i>dns.log</i>, <i>ssl.log</i>, <i>files.log</i>, <i>x509.log</i>). These logs are typically produced in tab-separated value (TSV) format, making them highly parsable and easily integrable with Security Information and Event Management (SIEM) systems, data lakes, or analytical platforms for further processing and correlation.


title: POWERFUL SCRIPTING LANGUAGE
content:
At the core of Zeek's flexibility is its custom, event-driven scripting language. This language enables users to define sophisticated detection logic, implement custom protocol analysis, maintain stateful information across connections, and react dynamically to network events. This capability allows for highly tailored security policies and deep insight into network behavior that generic signature-based systems cannot provide.


title: HISTORY
content:
Originally developed by Vern Paxson at Lawrence Berkeley National Laboratory (LBNL) in 1995 and open-sourced in 1996, the project was initially known as <b>Bro</b>. It quickly became a foundational tool in network security research and operations. In 2018, the project was officially renamed from Bro to <b>Zeek</b> to better reflect its expansive capabilities beyond simple monitoring and to adopt a more broadly appealing identity. It is now maintained and evolved by the Zeek Project, a community-driven open-source initiative.


title: PARAMETERS
content:
<b><I>grep_options</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Any valid options supported by the standard <I>grep</I> command (e.g., <B>-i</B> for case-insensitive search, <B>-v</B> for inverted match, <B>-l</B> for listing filenames only). These options are passed directly to <I>grep</I>.<br><br><b><B>PATTERN</B></b><br>&nbsp;&nbsp;&nbsp;&nbsp;The regular expression pattern to search for within the content of the files.<br><br><b><B>FILE</B>...</b><br>&nbsp;&nbsp;&nbsp;&nbsp;One or more files to search. These can be uncompressed or compressed files (e.g., <B>.gz</B>, <B>.bz2</B>, <B>.xz</B>, <B>.Z</B>). If no <B>FILE</B> is specified, <I>zegrep</I> reads from standard input, expecting compressed or uncompressed data.<br><br>


title: DESCRIPTION
content:
<I>zegrep</I> (often symlinked from <I>zgrep</I>) is a utility for searching text patterns within compressed files. It acts as a convenient wrapper around the standard <I>grep</I> command, automatically decompressing files on-the-fly before piping their content to <I>grep</I>. This eliminates the need for users to manually decompress files with tools like <I>gunzip</I> or <I>bunzip2</I> prior to searching.<br><br><I>zegrep</I> supports various compression formats, including those created by <I>gzip</I>, <I>compress</I>, <I>bzip2</I>, and <I>xz</I>, by dynamically detecting the file type and invoking the appropriate decompression utility (e.g., <I>gunzip -c</I>, <I>bunzip2 -c</I>, <I>xz -dc</I>). It passes all provided arguments, including <I>grep</I>'s specific options and the search pattern, directly to the underlying <I>grep</I> command, making its usage largely identical to <I>grep</I> itself, but extended to compressed data.


title: CAVEATS
content:
<ul><li><B>Performance Impact</B>: Searching compressed files involves on-the-fly decompression, which can be slower than searching uncompressed files directly, especially for very large files or slow CPUs.</li><li><B>Dependency</B>: <I>zegrep</I> relies on the presence of <I>grep</I> and the corresponding decompression utilities (like <I>gunzip</I>, <I>bunzip2</I>, <I>unxz</I>) to function correctly.</li><li><B>Memory Usage</B>: While it streams content, processing very large compressed files might still consume noticeable resources during decompression.</li></ul>


title: <B>ENVIRONMENT VARIABLES</B>
content:
<I>zegrep</I>'s behavior can be influenced by environment variables.<br><B>GREP</B>: Specifies the <I>grep</I> program to use instead of the default.<br><B>COMPRESS_PROGRAM</B>: Can be used to override the default decompression program (e.g., to force <I>gunzip</I> even if a <B>.bz2</B> file is encountered, though this might lead to errors if the file is not in <I>gzip</I> format).


title: <B>EXIT STATUS</B>
content:
The exit status of <I>zegrep</I> is typically the same as the exit status of the underlying <I>grep</I> command it invokes.<br><B>0</B>: One or more lines were selected.<br><B>1</B>: No lines were selected.<br><B>2</B>: An error occurred.


title: HISTORY
content:
<I>zegrep</I> (and its more common alias <I>zgrep</I>) is part of the <I>gzip</I> package, which was developed to provide tools for handling compressed files in a Unix-like environment. Its creation was motivated by the common need to search log files or other data archives that are frequently stored in compressed formats to save disk space. By automating the decompression step, <I>zegrep</I> significantly streamlined workflows for system administrators and developers who regularly interact with compressed data. It has been a standard utility in most Linux distributions for many years.


title: PARAMETERS
content:
<b><i>--verbose</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Prints diagnostic information to standard error during the conversion process, which can be useful for debugging or understanding the file structure of the Zeiss input.<br><br>


title: DESCRIPTION
content:
The <b>zeisstopnm</b> command is a utility within the <i>Netpbm</i> image processing suite, specifically designed to convert images from the Zeiss confocal microscope file format (LSM) into the Netpbm family of image formats.<br><br>It serves as a crucial bridge for scientists and researchers, enabling them to process their Zeiss microscopy data using a wide array of standard Unix/Linux image manipulation tools that are compatible with the PNM (Portable Anymap) format. The command handles both 8-bit grayscale Zeiss images, converting them to <i>PGM</i> (Portable Graymap) format, and 24-bit color images, converting them to <i>PPM</i> (Portable Pixmap) format.<br><br>Input can be provided either from a specified file or through standard input. The output PNM image is written to standard output. A notable feature is its ability to correctly handle multi-frame Zeiss files, such as time series or Z-stacks. When processing such files, <b>zeisstopnm</b> generates multiple output PNM files, automatically appending a sequential frame number to the base output filename.


title: CAVEATS
content:
This utility is specifically tailored for the <i>Zeiss LSM</i> (Laser Scanning Microscope) file format. It may not support other proprietary Zeiss image formats or variations. The output is strictly in <i>Netpbm</i> format (PGM or PPM), requiring further conversion with other <i>Netpbm</i> tools (e.g., <b>pnmtojpeg</b>, <b>pnmtops</b>) if different output formats are desired. When processing multi-frame files, <b>zeisstopnm</b> outputs multiple files with appended numerical suffixes, which then need to be managed externally for tasks like creating animations or composite images.


title: INPUT/OUTPUT BEHAVIOR
content:
By default, <b>zeisstopnm</b> reads its input from a specified <i>zeiss_file</i>. If no filename is provided, it reads from standard input. The resulting <i>PNM</i> image (<i>PGM</i> for grayscale, <i>PPM</i> for color) is written to standard output. When dealing with multi-frame <i>Zeiss</i> files (like time-lapses or Z-stacks), the command generates multiple <i>PNM</i> files, automatically appending a sequential frame number (e.g., <i>output_001.pnm</i>, <i>output_002.pnm</i>) to the base output filename.


title: SUPPORTED IMAGE TYPES
content:
The command intelligently distinguishes between different bit depths of <i>Zeiss</i> input files. For 8-bit grayscale images, it produces a <i>PGM</i> (Portable Graymap) file. For 24-bit color images, it generates a <i>PPM</i> (Portable Pixmap) file. This ensures accurate representation of the original image data within the <i>Netpbm</i> framework.


title: HISTORY
content:
<b>zeisstopnm</b> is a component of the comprehensive <i>Netpbm</i> project, a venerable suite of graphics utilities dating back to the early days of Unix. The <i>Netpbm</i> tools are renowned for their philosophy of converting various image formats into a common intermediate format (PNM) to facilitate chained processing. <b>zeisstopnm</b> was specifically developed and integrated into this suite to address the growing need for interoperability with image data produced by <i>Zeiss</i> confocal microscopes, a common instrument in biological and material sciences. Its inclusion reflects the <i>Netpbm</i> project's ongoing effort to support a wide array of scientific and proprietary image formats.


title: SYNOPSIS
content:
<b>zellij</b> [OPTIONS] [COMMAND]<br><b>zellij</b> [LAYOUT_FILE]<br><br><i>Common usage:</i><br><b>zellij</b> <i>attach</i> [SESSION_NAME]<br><b>zellij</b> <i>run</i> [COMMAND]<br><b>zellij</b> <i>options</i> [OPTION] [VALUE]<br><b>zellij</b> <i>list-sessions</i><br><b>zellij</b> <i>kill-session</i> [SESSION_NAME | --all]


title: PARAMETERS
content:
<b>-s, --session <NAME></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Attach to or create a session with the specified name. If no name is given, a default one is used.<br><br><b>--layout <FILE></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Start a new session using a predefined layout from the specified YAML file.<br><br><b>--no-pane-frames</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Start Zellij without drawing visual frames around the panes.<br><br><b>--disable-default-plugins</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Prevent Zellij from loading its default set of plugins at startup.<br><br><b>--debug</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Enable debug mode, providing more verbose output for troubleshooting.<br><br><b>--floating-panes</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Allow panes to 'float' or overlap other panes, providing more layout flexibility.<br><br><b>--plugin <URL></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Add a specific plugin to the current session from a local path or URL.<br><br><b>--dump-layout <PATH></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Dump the current session's layout configuration to the specified YAML file.<br><br><b>--data-dir <PATH></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specify a custom data directory for Zellij configurations and session files.<br><br>


title: DESCRIPTION
content:
<b>Zellij</b> is a powerful and opinionated terminal workspace multiplexer, akin to `tmux` or `GNU screen`, but written in <i>Rust</i>. It enables users to manage multiple terminal sessions, panes, and tabs within a single terminal window, providing a persistent and organized work environment. Key features include a robust declarative layout system (defined in YAML) for arranging panes, a plugin system based on <i>WebAssembly (Wasm)</i> for extending functionality, built-in scrolling, and collaborative session sharing capabilities.<br><br>Zellij aims to streamline the terminal workflow by offering a unified and highly customizable environment for development, system administration, and general command-line tasks. It automatically saves session states, allowing users to detach and re-attach later, resuming exactly where they left off. Its focus on discoverability, sensible defaults, and a modern user interface makes it accessible to new users while still providing advanced configuration options for experienced ones.


title: CAVEATS
content:
<b>Zellij</b> requires a modern terminal emulator (e.g., Alacritty, Kitty, WezTerm, iTerm2, etc.) to fully leverage its features, including true color support and advanced font rendering. Its configuration is primarily done via <i>YAML</i> files, which might require a different approach compared to `tmux`'s configuration files. While highly user-friendly, its opinionated default keyboard shortcuts and modal interface (similar to <i>vi/vim</i>) may require an adjustment period for users accustomed to other multiplexers. It is under active development, so features and behavior might evolve between versions.


title: PLUGINS AND WEBASSEMBLY (WASM)
content:
One of <b>Zellij's</b> most distinctive features is its support for plugins. These plugins are written in <i>WebAssembly (Wasm)</i>, allowing for powerful extensions to functionality directly within terminal panes. This enables users to integrate tools like file browsers, task managers, or custom widgets, significantly enhancing the interactive capabilities of the terminal workspace.


title: DECLARATIVE LAYOUT SYSTEM
content:
<b>Zellij</b> utilizes a sophisticated, declarative layout system defined in <i>YAML</i> files. Users can easily create and switch between complex arrangements of panes, tabs, and commands for different workflows. This allows for highly reproducible and shareable work environments, improving consistency and efficiency across projects or teams.


title: MODAL INTERFACE
content:
Inspired by text editors like <i>vi/vim</i>, <b>Zellij</b> operates with a modal interface. Users interact with the multiplexer by entering specific modes (e.g., <i>Pane</i> mode for manipulating panes, <i>Tab</i> mode for managing tabs, <i>Scroll</i> mode for navigating output) using a common prefix key (default: <i>Ctrl+b</i>). This approach provides intuitive and context-aware keybindings.


title: HISTORY
content:
<b>Zellij</b> was created by Zdravko Botev and first officially released in 2021. Developed in <i>Rust</i>, it emerged as a modern alternative to long-standing terminal multiplexers like <i>tmux</i> and <i>GNU screen</i>, aiming to provide better performance, memory safety, and a more intuitive user experience. It quickly gained traction due to its innovative built-in features, such as the declarative layout system, integrated plugin architecture (using <i>WebAssembly</i>), and collaborative session capabilities, distinguishing itself from its predecessors.


title: SYNOPSIS
content:
<b>zenity</b> <i>DIALOG_TYPE</i> [<i>DIALOG_OPTIONS</i>] [<i>GENERAL_OPTIONS</i>]<br><br>Example:<br><i>zenity --info --text="Hello, Zenity!" --title="My First Dialog"<br>zenity --entry --text="Enter your name:" --width=300<br>zenity --file-selection --multiple --directory</i>


title: PARAMETERS
content:
<b><b>--calendar</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays a calendar selection dialog.<br><br><b><b>--entry</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays a text entry dialog for user input.<br><br><b><b>--error</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays an error message dialog.<br><br><b><b>--file-selection</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays a file or directory selection dialog.<br><br><b><b>--info</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays an informational message dialog.<br><br><b><b>--list</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays a list dialog with selectable items.<br><br><b><b>--progress</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays a progress bar dialog.<br><br><b><b>--question</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays a question dialog, returning true/false.<br><br><b><b>--text=<I>text</I></b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets the main text/message for the dialog.<br><br><b><b>--title=<I>title</I></b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets the window title of the dialog.<br><br><b><b>--width=<I>pixels</I></b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets the dialog window width.<br><br><b><b>--height=<I>pixels</I></b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets the dialog window height.<br><br><b><b>--filename=<I>path</I></b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets the initial filename or directory for file selection.<br><br><b><b>--directory</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Allows selection of directories instead of files.<br><br><b><b>--multiple</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Allows selection of multiple files or items.<br><br><b><b>--timeout=<I>seconds</I></b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets a timeout after which the dialog closes automatically.<br><br>


title: DESCRIPTION
content:
<b>zenity</b> is a command-line tool that allows shell scripts and applications to interact with users graphically. It provides a simple way to create various common GTK+ dialog boxes, bypassing the need for complex GUI programming. These dialogs include information, error, warning, question, text entry, file selection, calendar, progress bars, list views, and forms. <br><br>As part of the GNOME project, <b>zenity</b> aims to empower script developers to add user-friendly graphical interfaces to their scripts without delving into graphical toolkit specifics. It outputs the user's choices or input to standard output (<i>stdout</i>), which can then be easily captured and processed by the script. This makes it an invaluable tool for creating interactive desktop scripts, automating tasks, or providing quick feedback to users.


title: CAVEATS
content:
<b>zenity</b> relies on a graphical desktop environment and the GTK+ toolkit; it cannot be used in a pure terminal (<i>TTY</i>) environment. Its functionality is focused on common dialog types, offering less customization than direct GTK+ programming. User input and selections are sent to standard output, requiring scripts to parse this output, which can be complex for multi-line inputs or filenames with special characters. While convenient, launching <b>zenity</b> incurs GUI overhead, making it potentially slower for very frequent or trivial interactions compared to purely command-line alternatives.


title: STANDARD OUTPUT FOR SCRIPTING
content:
One of <b>zenity</b>'s core features is its use of <i>standard output (stdout)</i> to return user input or choices. For example, a selected filename from <i>--file-selection</i>, entered text from <i>--entry</i>, or 'True'/'False' from <i>--question</i> are printed to stdout. This design allows shell scripts to easily capture and process the results using command substitution (e.g., <i>variable=$(zenity --entry)</i>), enabling dynamic script behavior based on user interaction.


title: DESKTOP ENVIRONMENT INTEGRATION
content:
<b>zenity</b> is tightly integrated with the user's desktop environment, particularly GNOME. This means dialogs inherit the system's GTK+ theme, ensuring a consistent look and feel. It also leverages desktop services, such as the notification daemon for <i>--notification</i> dialogs, providing a seamless user experience that is visually and functionally aligned with other native applications.


title: HISTORY
content:
<b>zenity</b> emerged as part of the <i>GNOME desktop environment</i>, specifically designed to replace older, less flexible tools like <i>gdialog</i>. It was introduced around the GNOME 2.2 release in 2003, providing a modern, GTK+ based solution for adding simple graphical interactions to shell scripts. Its development has focused on maintaining ease of use while integrating well with the GNOME desktop's look and feel, making it a staple for creating user-friendly scripts on Linux systems.


title: SYNOPSIS
content:
<b><I>zenmap</I></b> [<i>options</i>] [<i>target_spec</i>]<br><br>The <i>target_spec</i> typically refers to a hostname or IP address range, which <b><I>zenmap</I></b> passes directly to <b><I>Nmap</I></b>. While many <i>options</i> correspond to <b><I>Nmap</I></b> options, which <b><I>zenmap</I></b> passes through, it also possesses its own specific options that control its GUI behavior and startup.


title: PARAMETERS
content:
<b><b>--help</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays a help message showing available command-line options and exits.<br><br><b><b>--version</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays <b><I>zenmap</I></b>'s version information and exits.<br><br><b><b>--stylesheet</b> <i>&lt;path&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies an alternative stylesheet for the display of scan results, customizing the appearance.<br><br><b><b>--profile</b> <i>&lt;name&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Loads a previously saved scan profile by its specified name, pre-filling scan options in the interface.<br><br><b><b>--open-output</b> <i>&lt;filename&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Opens a specified <b><I>Nmap</I></b> output file (e.g., .xml, .nmap, .gnmap) upon startup, displaying its results.<br><br><b><b>--allow-root-commands</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Allows <b><I>Nmap</I></b> commands to be run as root without requiring a password prompt, potentially bypassing security measures (use with extreme caution).<br><br><b><b>--no-nmap-exec</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Prevents <b><I>zenmap</I></b> from actually executing <b><I>Nmap</I></b>; it will only display the <b><I>Nmap</I></b> command that would have been run.<br><br><b><b>--force-gui</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Forces <b><I>zenmap</I></b> to start its graphical interface even in environments where it might typically fail (e.g., lacking an X server).<br><br>


title: DESCRIPTION
content:
<b><I>zenmap</I></b> is the official graphical user interface (GUI) for the <b><I>Nmap</I></b> Security Scanner. It's a cross-platform application designed to make <b><I>Nmap</I></b> easier to use for beginners while providing advanced features for experienced users. <b><I>zenmap</I></b> allows users to perform network scans, save and compare scan results, and visualize network topology.<br><br>It includes a profile system for commonly used scans, a results viewer, and a powerful search function for previous scan results. <b><I>zenmap</I></b> translates user inputs into <b><I>Nmap</I></b> commands and executes them, then parses the <b><I>Nmap</I></b> output to display it in a user-friendly format. It aims to simplify complex <b><I>Nmap</I></b> operations and provides a visual representation of network discovery, making it a valuable tool for network administrators and security professionals.


title: CAVEATS
content:
<b><I>zenmap</I></b> requires <b><I>Nmap</I></b> to be installed and accessible in the system's PATH for its core functionality. As a GUI application, it necessitates a graphical environment (like X Window System on Linux) to run. Running extensive network scans or attempting to visualize very large and complex networks can consume significant system resources (CPU, memory), potentially leading to performance issues. While user-friendly, some highly advanced or esoteric <b><I>Nmap</I></b> features might be less intuitive to configure via the GUI compared to direct command-line usage. The <b>--allow-root-commands</b> option, while convenient, can pose significant security risks if used carelessly.


title: NMAP INTEGRATION
content:
<b><I>zenmap</I></b> is fundamentally a sophisticated wrapper around the command-line <b><I>Nmap</I></b> tool. All network scans initiated through <b><I>zenmap</I></b> are internally translated into standard <b><I>Nmap</I></b> commands, and the results are then meticulously parsed from <b><I>Nmap</I></b>'s XML output to be presented in a graphical format. This tight integration means that <b><I>zenmap</I></b>'s capabilities and available scanning options are directly tied to the version and features of the underlying <b><I>Nmap</I></b> installation.


title: NETWORK TOPOLOGY MAPPING
content:
One of <b><I>zenmap</I></b>'s most distinctive and useful features is its ability to visualize network topology based on the discovery results obtained from <b><I>Nmap</I></b>. It can graphically display discovered hosts, their estimated connections, and identify potential network pathways between them. This visual representation can be invaluable for understanding complex network layouts, identifying unknown devices, and pinpointing potential vulnerabilities in a more intuitive way than raw text output.


title: HISTORY
content:
<b><I>zenmap</I></b> was developed as an official front-end for the powerful <b><I>Nmap</I></b> network scanner, aiming to provide a user-friendly graphical interface. It was first released as part of the <b><I>Nmap</I></b> suite, specifically accompanying <b><I>Nmap</I></b> 4.20 in 2006. The project's goal was to broaden <b><I>Nmap</I></b>'s accessibility to a wider audience, including those less comfortable with the command line, and to offer visual tools for network discovery and analysis. Since its inception, <b><I>zenmap</I></b> has been consistently bundled with <b><I>Nmap</I></b> releases, evolving alongside <b><I>Nmap</I></b>'s capabilities and maintaining its role as the premier graphical interface for network scanning.


title: PARAMETERS
content:
<b><i>grep_options</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;<b>zfgrep</b> passes all command-line options directly to the underlying <b>grep</b> command (or <b>zgrep</b>, which in turn passes them to <b>grep</b>). Therefore, it supports the full range of <b>grep</b> options to control search behavior, output format, and file processing. Some commonly used options include:<br><b>-i</b>, <b>--ignore-case</b>: Ignore case distinctions in the <i>pattern</i> and input data.<br><b>-v</b>, <b>--invert-match</b>: Select non-matching lines.<br><b>-l</b>, <b>--files-with-matches</b>: Suppress normal output; instead print the name of each input file from which output would normally have been printed.<br><b>-n</b>, <b>--line-number</b>: Prefix each line of output with the 1-based line number within its input file.<br><b>-r</b>, <b>--recursive</b>: Read all files under each directory, recursively.<br><b>-E</b>, <b>--extended-regexp</b>: Interpret <i>pattern</i> as an extended regular expression (normally <b>zfgrep</b> uses fixed strings, but this overrides it).<br><b>-P</b>, <b>--perl-regexp</b>: Interpret <i>pattern</i> as a Perl regular expression.<br><b>-c</b>, <b>--count</b>: Suppress normal output; instead print a count of matching lines for each input file.<br><br><b><i>pattern</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;The fixed string to search for within the files. By default, <b>zfgrep</b> treats this as a literal string (no regular expression interpretation).<br><br><b><i>file ...</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;One or more compressed or uncompressed files to search. If no files are specified, <b>zfgrep</b> reads from standard input. If a file ends with a known compression suffix (.gz, .bz2, .xz, etc.), it is automatically decompressed before searching.<br><br>


title: DESCRIPTION
content:
The <b>zfgrep</b> command is a utility that allows users to search for fixed strings within compressed files. It functions as a wrapper around the standard <b>grep</b> command, automatically decompressing files on-the-fly and piping their content to <b>grep</b>. It is typically implemented as an alias or hard link to <b>zgrep -F</b>, meaning it performs a fixed string search (non-regular expression) by default. <b>zfgrep</b> can handle various common compression formats, including <b>gzip</b> (.gz), <b>bzip2</b> (.bz2), <b>xz</b> (.xz), <b>lzma</b> (.lzma), <b>compress</b> (.Z), and often <b>zstd</b> (.zst), making it a versatile tool for querying logs and data archives without prior manual decompression.<br><br>Its primary advantage lies in saving disk space by allowing direct search on compressed data, while its main distinction from <b>zgrep</b> is its default behavior of treating the <i>pattern</i> as a literal string rather than a regular expression.


title: CAVEATS
content:
Performance can be impacted as files must be decompressed on the fly, which consumes CPU and I/O resources, especially for very large compressed files.<br>Requires the corresponding decompression utilities (e.g., <b>gzip</b>, <b>bzip2</b>, <b>xz</b>) to be installed on the system for each compressed file type it encounters.<br>By default, it performs a fixed string search (<b>-F</b>). If regular expression matching is desired, you must explicitly use <b>-E</b> or <b>-P</b> (or other regex options), or use the <b>zgrep</b> command directly.


title: DEFAULT BEHAVIOR
content:
<b>zfgrep</b> is functionally equivalent to executing <b>zgrep -F</b>. This means that, unlike plain <b>grep</b> or <b>zgrep</b> which default to basic regular expressions, <b>zfgrep</b> treats the search <i>pattern</i> as a literal string. This is particularly useful when searching for text that might contain special regular expression characters (e.g., '.', '*', '[', ']') which you want to match literally without needing to escape them.


title: SUPPORTED COMPRESSION FORMATS
content:
<b>zfgrep</b> dynamically detects and handles files compressed with common utilities based on their filename suffixes. This includes <b>.gz</b> (gzip), <b>.bz2</b> (bzip2), <b>.xz</b> (xz), <b>.lzma</b> (lzma), <b>.Z</b> (compress), and sometimes <b>.zst</b> (zstd). It transparently pipes the decompressed output of these files into <b>grep</b>, allowing seamless searching across various compressed file types.


title: HISTORY
content:
<b>zfgrep</b> is typically distributed as part of the <b>gzip</b> package (or sometimes <b>zutils</b>) along with other <b>z*</b> utilities like <b>zcat</b>, <b>zless</b>, and <b>zgrep</b>. The <b>zgrep</b> utility was developed to extend <b>grep</b>'s functionality to compressed files. <b>zfgrep</b> was later introduced as a convenience wrapper, specifically often implemented as a hard link or script calling <b>zgrep -F</b>. This provides a dedicated command for fixed-string searches on compressed data without needing to explicitly remember the <b>-F</b> option, which is particularly useful for literal text searches in log files and data archives.


title: SEE ALSO
content:
<b>grep(1)</b>: The general purpose text search utility for plain files., <b>zgrep(1)</b>: Search compressed files for regular expressions (default is regex, not fixed string)., <b>gzcat(1)</b>: Concatenate compressed files to standard output (often used for simple decompression)., <b>bzip2(1)</b>: A block-sorting file compressor., <b>xz(1)</b>: A command-line tool for compressing or decompressing .xz files.


title: PARAMETERS
content:
<b><b>-r</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Recursively applies the force-readonly operation to all descendant filesystems within the specified pool or dataset.<br><br><b><i>filesystem</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;The name of the ZFS filesystem or pool to operate on. If a pool is specified without <b>-r</b>, only the top-level dataset of the pool is affected.<br><br>


title: DESCRIPTION
content:
<i>zforce</i> is a ZFS utility command used to force a ZFS filesystem or an entire pool's filesystems into a read-only state. This command is primarily employed in scenarios where a ZFS filesystem is marked as writable but cannot be mounted read-write due to underlying issues like corruption, errors, or a degraded/faulted pool.<br><br>By setting the `readonly` property, <i>zforce</i> allows administrators to potentially import a problematic pool or mount a specific filesystem in a safe, read-only mode for diagnostic purposes or data extraction, even if it's otherwise unmountable. It does not perform any data repair or modification; it simply changes the filesystem's metadata property to prevent writes, thus avoiding further damage or mount failures. This is often a critical step in a recovery process for damaged ZFS datasets.


title: CAVEATS
content:
<i>zforce</i> does not actually mount the filesystem; it merely modifies the `readonly` property of the dataset's metadata. The pool containing the filesystem must be imported, even if it's in a degraded or faulted state, for <i>zforce</i> to operate.<br><br>This command is considered a last-resort tool for problematic datasets. Misuse or incorrect application can prevent legitimate write access until the `readonly` property is manually reverted using `<b>zfs set readonly=off</b> <i>filesystem</i>`. Always exercise caution as it can impact data integrity if not used properly in a recovery context. Root privileges are required to execute this command.


title: <B>USAGE SCENARIO</B>
content:
Imagine a ZFS pool that is degraded and you cannot mount a specific filesystem because it claims to be writable but the underlying storage issues prevent writes. Running `<b>zforce</b> <i>mypool/myfilesystem</i>` would set that filesystem's `readonly` property to `on`, allowing you to then attempt to mount it read-only, potentially recovering data or diagnosing the issue without risking further corruption.


title: <B>REVERTING READ-ONLY STATE</B>
content:
To revert a filesystem from the read-only state imposed by <i>zforce</i>, you must manually set the `readonly` property back to `off` using the command: `<b>zfs set readonly=off</b> <i>filesystem_name</i>`. This can only be done once the underlying issues preventing write access have been resolved.


title: HISTORY
content:
<i>zforce</i> is an integral part of the ZFS filesystem utilities. ZFS, originally developed by Sun Microsystems, was open-sourced as OpenZFS after Oracle acquired Sun. The <i>zforce</i> command emerged as a necessary tool within the ZFS ecosystem to handle difficult recovery scenarios for datasets, evolving with the robust and complex nature of ZFS itself. Its functionality has remained consistent as ZFS matured across various Unix-like operating systems.


title: SYNOPSIS
content:
<b>zfs</b> [<i>options</i>] <i>subcommand</i> [<i>subcommand-options</i>] [<i>arguments</i>]<br><br><i>Examples:</i><br><b>zfs create</b> <i>pool/dataset_name</i><br><b>zfs list</b> <i>pool/dataset_name</i><br><b>zfs destroy</b> <i>pool/dataset_name</i><br><b>zfs snapshot</b> <i>pool/dataset_name@snapshot_name</i><br><b>zfs send</b> <i>pool/dataset_name@snapshot_name</i> | <b>ssh</b> <i>remote_host</i> <b>zfs receive</b> <i>remote_pool</i>


title: PARAMETERS
content:
<b><b>create</b> <i>dataset</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Creates a new ZFS dataset (filesystem or volume) within a specified pool or parent dataset.<br><br><b><b>destroy</b> <i>dataset</i> | <i>snapshot</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Destroys the specified dataset or snapshot, permanently removing its data. <i>Use with extreme caution.</i><br><br><b><b>list</b> [<i>-t type</i>] [<i>-r</i>] [<i>-o properties</i>]</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Lists ZFS datasets and their properties. Can be filtered by type or display specific properties.<br><br><b><b>snapshot</b> <i>dataset@snapshot</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Creates a read-only snapshot of a dataset at a specific point in time. Snapshots are very efficient.<br><br><b><b>rollback</b> <i>dataset@snapshot</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Reverts a dataset to a previous state defined by a snapshot, destroying any data created after the snapshot.<br><br><b><b>send</b> <i>snapshot</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Generates a stream representation of a ZFS snapshot, typically used for replication or backup.<br><br><b><b>receive</b> <i>pool</i> | <i>dataset</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Receives a ZFS stream, typically from <b>zfs send</b>, to recreate or update a dataset on the receiving system.<br><br><b><b>set</b> <i>property=value dataset</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets a ZFS property on a dataset (e.g., compression, quota, mountpoint).<br><br><b><b>get</b> [<i>-r</i>] [<i>-p</i>] [<i>all</i> | <i>property</i>] <i>dataset</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Retrieves the value of ZFS properties for a dataset or all datasets.<br><br><b><b>clone</b> <i>snapshot dataset</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Creates a writable clone of a read-only snapshot. Clones are initially space-efficient.<br><br><b><b>rename</b> <i>old_name new_name</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Renames a ZFS dataset or snapshot.<br><br><b><b>hold</b> <i>tag snapshot</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Places a user-defined hold on a snapshot, preventing it from being destroyed until released.<br><br><b><b>release</b> <i>tag snapshot</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Removes a user-defined hold from a snapshot.<br><br><b><b>diff</b> <i>snapshot_A snapshot_B</i> | <i>snapshot_A dataset</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays the differences between a snapshot and its current state or another snapshot.<br><br>


title: DESCRIPTION
content:
ZFS is an advanced filesystem and logical volume manager known for its robust data integrity, massive scalability, and powerful features like snapshots, clones, and integrated RAID-Z. The <b>zfs</b> command is the primary tool used to interact with ZFS filesystems (also known as datasets), manage their properties, create and destroy snapshots, and perform replication operations.<br><br>It allows administrators to create, manage, and inspect the hierarchical structure of ZFS datasets, which can represent filesystems, volumes (block devices), or zvols. With <b>zfs</b>, users can control various aspects of their data storage, including compression, deduplication, quotas, and access control lists, making it a comprehensive solution for enterprise-grade storage management.


title: CAVEATS
content:
<ul><li><b>zfs</b> operations often require <i>root privileges</i> or membership in a privileged group.</li><li>The <b>destroy</b> subcommand is <i>irreversible</i> and can lead to immediate data loss if used incorrectly. Always double-check the target dataset.</li><li>ZFS datasets typically manage their own mounting; manual <b>mount</b> commands are usually unnecessary and can conflict with ZFS's auto-mounting.</li><li>While powerful, ZFS has a <i>steep learning curve</i> due to its extensive features and property system.</li><li>Performance tuning and optimal configuration can be complex and workload-dependent.</li></ul>


title: ZFS PROPERTIES
content:
ZFS datasets have numerous configurable <i>properties</i> (e.g., <i>compression</i>, <i>dedup</i>, <i>quota</i>, <i>mountpoint</i>). These properties can be inherited from parent datasets and control various aspects of data storage and behavior. They are managed using the <b>zfs set</b> and <b>zfs get</b> subcommands.


title: SNAPSHOTS AND CLONES
content:
ZFS offers highly efficient <i>snapshots</i>, which are read-only copies of a dataset at a specific point in time, consuming virtually no extra space initially. From snapshots, writable <i>clones</i> can be created. This feature is invaluable for backups, testing environments, and data versioning.


title: REPLICATION WITH SEND/RECEIVE
content:
The <b>zfs send</b> and <b>zfs receive</b> subcommands enable powerful and efficient data replication. They can send incremental or full snapshots of datasets over a network, making them ideal for offsite backups, disaster recovery, and migrating ZFS data between systems.


title: HIERARCHICAL DESIGN
content:
ZFS datasets are organized hierarchically, allowing for nested filesystems. Properties can be inherited down the hierarchy, simplifying management and enabling fine-grained control over different parts of your storage.


title: HISTORY
content:
ZFS was originally designed and implemented by Sun Microsystems (now Oracle) for its Solaris operating system, with the first version released in 2005. It was innovative for its features like copy-on-write, end-to-end data integrity, and pooled storage. After Sun's acquisition by Oracle, the open-source development of ZFS continued under the OpenSolaris project. The Linux port, initially known as ZFS on Linux (ZoL), began in 2010, aiming to bring ZFS's robust capabilities to the Linux ecosystem. This project eventually became a part of the broader OpenZFS initiative, which unites various open-source ZFS implementations to ensure compatibility and foster collaborative development across different operating systems like Linux, FreeBSD, macOS, and Windows.


title: SEE ALSO
content:
<b>zpool</b>(8): Manages ZFS storage pools, which are the underlying storage for ZFS datasets. This is the companion command to <b>zfs</b>., <b>zdb</b>(8): A ZFS diagnostic and debugging utility, typically used for advanced troubleshooting., <b>mount</b>(8): Though ZFS datasets auto-mount, <b>mount</b> can be used to manually mount if the <i>mountpoint</i> property is set to <i>legacy</i>., <b>df</b>(1): Can be used to view space usage of mounted ZFS filesystems.


title: SYNOPSIS
content:
<I><B>zgrep</B> [<I>grep_options</I>] [ <B>-e</B> <I>pattern</I> | <B>-f</B> <I>file</I> ] [ <B>--</B> ] [<I>file ...</I>]</I>


title: PARAMETERS
content:
<b><B>pattern</B></b><br>&nbsp;&nbsp;&nbsp;&nbsp;<I>The regular expression or fixed string to search for within the files.</I><br><br><b><B>file ...</B></b><br>&nbsp;&nbsp;&nbsp;&nbsp;<I>One or more compressed or uncompressed files to search. If no files are specified, <B>zgrep</B> reads from standard input (e.g., piped output from <B>zcat</B>).</I><br><br><b><B>-e</B> <I>pattern</I>, <B>--regexp=</B><I>pattern</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;<I>Use <B>PATTERN</B> as a pattern. This option is useful for specifying multiple search patterns or for protecting patterns that begin with a hyphen (<B>-</B>).</I><br><br><b><B>-f</B> <I>file</I>, <B>--file=</B><I>file</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;<I>Obtain patterns from <B>FILE</B>, with one pattern per line. Blank lines in <B>FILE</B> match no lines.</I><br><br><b><B>--</B></b><br>&nbsp;&nbsp;&nbsp;&nbsp;<I>Marks the end of options. Any arguments following <B>--</B> are treated as filenames, even if they start with a hyphen.</I><br><br><b><I>[grep_options]</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;<I><B>zgrep</B> passes most options directly to the underlying <B>grep</B> command. Common <B>grep</B> options like <B>-i</B> (ignore case), <B>-l</B> (list matching files), <B>-n</B> (show line numbers), <B>-c</B> (count matches), or <B>-v</B> (invert match) are fully supported.</I><br><br>


title: DESCRIPTION
content:
<I><B>zgrep</B> is a powerful utility that allows users to search for patterns within compressed files without the need for manual decompression. It acts as a convenient wrapper around the standard <B>grep</B> command, automatically detecting and decompressing files compressed with various popular utilities such as <B>gzip</B>, <B>bzip2</B>, <B>xz</B>, <B>lzip</B>, and <B>lzma</B>.<br><br>This command is particularly valuable for system administrators and developers who frequently work with log files, archives, or other data that are stored in a compressed format to conserve disk space. When <B>zgrep</B> encounters a compressed file, it seamlessly decompresses its content on-the-fly and pipes the output to <B>grep</B>. All options that are valid for <B>grep</B> are generally applicable to <B>zgrep</B>, as they are passed directly to the underlying <B>grep</B> process. This integration makes <B>zgrep</B> an essential tool for efficient text searching in compressed data streams, saving both time and disk resources.</I>


title: CAVEATS
content:
<I><B>Performance Overhead</B>: While convenient, decompressing files on-the-fly can introduce a slight performance overhead compared to searching already decompressed files, especially for very large datasets or high volume operations.<br><br><B>Dependency on Decompression Utilities</B>: <B>zgrep</B> relies on the presence of the corresponding decompression utilities (<B>gzip</B>, <B>bzip2</B>, <B>xz</B>, etc.) on the system. If a specific utility is missing, files compressed with that method cannot be searched.<br><br><B>Error Handling</B>: Errors during the decompression process (e.g., corrupted compressed files) might cause <B>zgrep</B> to terminate prematurely or produce incomplete results.</I>


title: <B>SUPPORTED COMPRESSION FORMATS</B>
content:
<I><B>zgrep</B> automatically detects and handles files compressed with various common algorithms, including <B>.gz</B> (gzip), <B>.bz2</B> (bzip2), <B>.xz</B> (xz), <B>.lz</B> (lzip), and <B>.lzma</B> (lzma). This detection is typically based on file extensions and/or magic numbers embedded within the file.<br></I>


title: <B>ENVIRONMENT VARIABLES</B>
content:
<I>The behavior of <B>zgrep</B> can be influenced by environment variables that affect the underlying <B>grep</B> command. Examples include <B>GREP_OPTIONS</B> (to set default <B>grep</B> options), <B>GREP_COLOR</B> (for output coloring), and <B>PAGER</B> (to define the program used to paginate output for large results).</I>


title: HISTORY
content:
<I><B>zgrep</B> emerged as part of the <B>gzip</B> project, initiated by Jean-loup Gailly and Mark Adler. Its development was driven by the increasing need to efficiently manage and search through compressed data, particularly log files and archives, which became a common practice to save disk space. By acting as a simple shell script wrapper around <B>grep</B>, <B>zgrep</B> provided a seamless way to extend <B>grep</B>'s powerful pattern-matching capabilities to compressed files, integrating smoothly into existing Unix/Linux workflows and quickly becoming a standard utility for system administrators.</I>


title: SYNOPSIS
content:
zile [<i>OPTION</i>]... [<i>FILE</i>]...<br><br><i>Example usage:</i><br>zile myfile.txt<br>zile -q script.sh<br>zile +10 config.ini


title: PARAMETERS
content:
<b>-h, --help</b><br>&nbsp;&nbsp;&nbsp;&nbsp;<i>Displays a help message and exits.</i><br><br><b>-v, --version</b><br>&nbsp;&nbsp;&nbsp;&nbsp;<i>Outputs the version information and exits.</i><br><br><b>-q, --no-init-file</b><br>&nbsp;&nbsp;&nbsp;&nbsp;<i>Prevents loading the user's ~/.zile initialization file.</i><br><br><b>-f <i>FUNCTION</i>, --function=<i>FUNCTION</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;<i>Executes the specified FUNCTION upon startup.</i><br><br><b>-l <i>FILE</i>, --load=<i>FILE</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;<i>Loads and executes the commands from FILE at startup.</i><br><br><b>-x, --no-splash</b><br>&nbsp;&nbsp;&nbsp;&nbsp;<i>Suppresses the display of the splash screen on startup.</i><br><br><b>-r, --read-only</b><br>&nbsp;&nbsp;&nbsp;&nbsp;<i>Opens files in read-only mode, preventing accidental modifications.</i><br><br><b>+<i>LINE</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;<i>Opens the file and positions the cursor at the specified LINE number.</i><br><br><b>+<i>LINE</i>:<i>COLUMN</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;<i>Opens the file and positions the cursor at the specified LINE and COLUMN number.</i><br><br>


title: DESCRIPTION
content:
<b>zile</b> (Zile Is Lossy Emacs) is a compact and efficient text editor designed to mimic the core functionalities and keybindings of GNU Emacs, but with a significantly smaller footprint. It provides a familiar Emacs-like editing experience for users who require a lightweight editor, particularly in resource-constrained environments or when a full Emacs installation is impractical.<br><br>While not a complete replacement for GNU Emacs, <b>zile</b> excels at basic to intermediate text editing tasks, offering features like syntax highlighting, buffer management, and Emacs-style keyboard shortcuts. Its design prioritizes speed and simplicity, making it an excellent choice for quick edits, script development, or use on embedded systems and minimal installations. It's a testament to providing powerful editing capabilities without the overhead of a larger suite.


title: CAVEATS
content:
<b>zile</b> is designed as a lightweight Emacs clone, which means it implements a subset of GNU Emacs features. Users accustomed to the full GNU Emacs might find certain advanced functionalities, extensive Emacs Lisp capabilities, or specific modes missing or simplified. It's primarily suited for command-line environments and basic to intermediate text editing, rather than as a full-fledged IDE replacement.


title: EMACS COMPATIBILITY AND KEYBINDINGS
content:
<b>zile</b> strives to be highly compatible with GNU Emacs keybindings, allowing users familiar with Emacs to quickly adapt. Common commands like <b>C-x C-s</b> (save), <b>C-x C-f</b> (open file), <b>C-g</b> (cancel), and cursor movement keys (<b>C-f</b>, <b>C-b</b>, <b>C-n</b>, <b>C-p</b>) function as expected. This design choice minimizes the learning curve for Emacs users and maximizes productivity in a lightweight environment.


title: EXTENSIBILITY
content:
Although not supporting full Emacs Lisp, <b>zile</b> offers a simple, built-in scripting language that allows for customization and basic extensibility. Users can write simple functions and macros in their <b>~/.zile</b> initialization file to tailor the editor to their preferences or automate repetitive tasks, enhancing its utility beyond basic editing.


title: HISTORY
content:
<b>zile</b> emerged as part of the GNU project, with its initial release aimed at providing a smaller, faster, and simpler alternative to the increasingly feature-rich and resource-intensive GNU Emacs. Its development focused on retaining the essential Emacs editing paradigms and keybindings while shedding less frequently used or highly complex features.<br><br>This philosophy allowed <b>zile</b> to serve as a valuable tool for system administrators, developers on minimal systems, or anyone preferring a quick-loading, terminal-based Emacs experience without the overhead of a full Emacs installation. It represents a commitment to versatility within the GNU ecosystem.


title: PARAMETERS
content:
<b>--url <URL></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the URL of the ZincSearch server to connect to. E.g., <I>http://localhost:4080</I><br><br><b>--username <USER></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets the username for authenticating with the ZincSearch server.<br><br><b>--password <PASS></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Provides the password for authentication with the ZincSearch server.<br><br><b>--output-format <FORMAT></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Defines the output format for command results. Common formats include <I>json</I>, <I>yaml</I>, or <I>text</I>.<br><br><b>--config <FILE></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies an alternative configuration file for Zinc CLI settings, overriding default values.<br><br><b>-h, --help</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays the help message for the <b>zinc</b> command or a specific subcommand.<br><br><b>-v, --version</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Shows the current version of the Zinc CLI tool.<br><br>


title: DESCRIPTION
content:
Zinc, invoked via the <b>zinc</b> command, is a powerful command-line interface (CLI) for interacting with a ZincSearch server. ZincSearch is an open-source, full-text search engine designed to be a lightweight alternative to more complex search solutions. The <b>zinc</b> CLI allows users to perform a wide range of operations directly from the terminal, including managing search indexes (creating, listing, deleting), ingesting and manipulating documents, executing search queries, and retrieving server status. It provides a programmatic and scriptable way to administer the ZincSearch engine, making it invaluable for developers and system administrators who need to automate tasks, integrate with other systems, or perform quick data operations without relying on a graphical user interface or direct API calls. While it's a client-side tool, its robust functionality makes it a central component for managing ZincSearch deployments.


title: CAVEATS
content:
The <b>zinc</b> command is a client-side tool and requires a running ZincSearch server to be fully functional. It is typically installed via <I>pip</I> (as part of the <I>zinc-cli</I> Python package) or specific distribution packages, and is not a standard utility bundled with most Linux distributions by default. Its functionality is entirely dependent on the availability and configuration of the ZincSearch server. Users should also note that subcommands and their specific options can vary; using <I>--help</I> with specific subcommands is often necessary for detailed usage information.


title: COMMON SUBCOMMANDS
content:
The <b>zinc</b> command operates through a variety of subcommands, each designed for specific categories of operations. These subcommands often have their own unique sets of options and arguments. To explore the options for a specific subcommand, use <b>zinc</b> <I>subcommand</I> <I>--help</I>.<br><br>Some common subcommands include:<br><ul><li><b>zinc index create <I>index_name</I></b>: Creates a new search index on the server.</li><li><b>zinc document put <I>index_name</I> <I>document_id</I> -d '{"key":"value"}'</b>: Adds or updates a single document within a specified index.</li><li><b>zinc document bulk <I>index_name</I> -i <I>data.json</I></b>: Ingests multiple documents from a file into an index.</li><li><b>zinc query search <I>index_name</I> -q 'search term'</b>: Executes a full-text search query against an index.</li><li><b>zinc server info</b>: Retrieves detailed information and status about the connected ZincSearch server.</li></ul>


title: HISTORY
content:
The <b>zinc</b> command, specifically referring to the <I>zinc-cli</I> tool, emerged as a dedicated command-line interface for the ZincSearch project. ZincSearch itself was developed as an open-source, self-hosted full-text search engine, aiming to provide a more lightweight and simpler alternative to established solutions like Elasticsearch. The CLI was created to facilitate scriptable and direct interaction with ZincSearch servers, addressing the need for automation of administrative tasks, data ingestion, and querying without the overhead of a web UI or direct API calls. Its development closely mirrors the evolution and adoption of the ZincSearch engine, serving as a crucial component in its ecosystem for efficient management and operation.


title: SYNOPSIS
content:
<b>zint</b> [<i>OPTIONS</i>] <b>-o</b> <i>&lt;output_file&gt;</i> [<b>-d</b> <i>&lt;data_string&gt;</i> | <b>-i</b> <i>&lt;input_file&gt;</i>]


title: PARAMETERS
content:
<b><b>-b</b> <i>&lt;symbology_id&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets the barcode symbology to be used. Refer to <i>zint</i> documentation or run <i>zint -L</i> for a complete list of numeric IDs (e.g., 47 for QR Code, 2 for EAN-13).<br><br><b><b>-d</b> <i>&lt;data_string&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the data to be encoded in the barcode directly as a string.<br><br><b><b>-i</b> <i>&lt;input_file&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Reads the data to be encoded from the specified input file. Each line can represent a separate data item for batch processing.<br><br><b><b>-o</b> <i>&lt;output_file&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets the output filename for the generated barcode. The file extension determines the output format (e.g., <i>.png</i> for PNG, <i>.svg</i> for SVG, <i>.eps</i> for EPS).<br><br><b><b>-h</b> <i>&lt;height&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets the height of the barcode in modules. This option is specific to 1D barcodes and some 2D codes with variable height.<br><br><b><b>-w</b> <i>&lt;width&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets the width of the barcode in modules.<br><br><b><b>-s</b> <i>&lt;scale&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets the scaling factor for the barcode. A value of 1.0 means default size, 2.0 means double size.<br><br><b><b>-t</b> <i>&lt;text&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies human-readable text to be displayed below the barcode, overriding the default if not empty.<br><br><b><b>-x</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Hides the human-readable text below the barcode.<br><br><b><b>-v</b> <i>&lt;version&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets the symbol version or error correction level for 2D barcodes (e.g., QR Code, Aztec Code). Higher values mean more error correction or data capacity.<br><br><b><b>-F</b> <i>&lt;hex_color&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets the foreground (bar) color of the barcode in hexadecimal RGB (e.g., 000000 for black).<br><br><b><b>-B</b> <i>&lt;hex_color&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets the background color of the barcode in hexadecimal RGB (e.g., FFFFFF for white).<br><br><b><b>-r</b> <i>&lt;degrees&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Rotates the barcode image by the specified degrees (0, 90, 180, 270).<br><br><b><b>-m</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Adds quiet zones (white margins) around the barcode, which are crucial for reliable scanning.<br><br><b><b>-S</b> <i>&lt;option&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets specific symbol options (e.g., <i>gs1</i> for GS1 symbologies, <i>square</i> for square 2D modules, <i>invert</i> to invert colors).<br><br>


title: DESCRIPTION
content:
<i>zint</i> is an open-source barcode encoding library and command-line utility designed to generate a comprehensive range of 1D (linear) and 2D (matrix) barcode symbologies. It supports popular types like QR Code, Data Matrix, Aztec Code, EAN, UPC, Code 128, GS1 DataBar, and many more. Users can specify the input data directly or from a file, select the desired barcode type using a numeric ID, and define the output filename. The output format (e.g., PNG, SVG, EPS) is automatically determined by the file extension of the specified output file. <i>zint</i> is highly versatile, capable of generating high-quality vector and raster images suitable for printing, web applications, or any data encoding task. Its flexibility and extensive symbology support make it an invaluable tool for developers and users needing to create barcodes programmatically or from the command line.


title: CAVEATS
content:
<i>zint</i> relies on external libraries for certain image output formats (e.g., <i>libpng</i> for PNG, <i>librsvg</i> for SVG, <i>libtiff</i> for TIFF). Ensure these dependencies are installed for full functionality. The numeric symbology IDs can be extensive and require consulting the <i>zint</i> documentation or using the <b>-L</b> option to list them. Output format is strictly determined by the <b>-o</b> filename's extension.


title: SUPPORTED OUTPUT FORMATS
content:
<i>zint</i> can output barcodes in various raster and vector formats, determined by the output file's extension specified with <b>-o</b>. Common formats include: <br><b>PNG</b> (.png), <b>SVG</b> (.svg), <b>EPS</b> (.eps), <b>TIFF</b> (.tif, .tiff), <b>BMP</b> (.bmp), <b>GIF</b> (.gif), <b>JPEG</b> (.jpg, .jpeg), <b>PCX</b> (.pcx), <b>WMF</b> (.wmf), <b>EMF</b> (.emf), <b>ASCII</b> (.txt for ASCII art), <b>PostScript</b> (.ps).


title: SYMBOLOGY IDS
content:
To use <i>zint</i> effectively, understanding the numeric IDs for each barcode symbology is crucial. These IDs are passed with the <b>-b</b> option. For instance, '2' represents EAN-13, '47' represents QR Code, '58' represents Data Matrix, and '70' represents Code 128. A full list can typically be found in the <i>zint</i> documentation or by running <i>zint -L</i>.


title: HISTORY
content:
<i>zint</i> was initially developed by Robin Stuart, with its first public release around 2005. It was created to provide a comprehensive, open-source, and cross-platform solution for barcode generation, addressing the need for a tool that supports a broader range of symbologies than many existing options. Written primarily in C, it has since grown into a robust library and command-line utility, widely adopted in various applications for its reliability and extensive feature set.


title: PARAMETERS
content:
<b><b>-r</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;<I>Recurse</I> into directories. When files are specified, this option will add all files and subdirectories within them.<br><br><b><b>-u</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;<I>Update</I> an existing archive. Adds new files and replaces older versions of files already in the archive.<br><br><b><b>-f</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;<I>Freshen</I> existing files. Updates only those files that have changed since they were last added to the archive. Does not add new files.<br><br><b><b>-d</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;<I>Delete</I> entries from a zip archive. Files specified are removed from the archive.<br><br><b><b>-m</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;<I>Move</I> files into zip archive. After successful compression, the original files are deleted.<br><br><b><b>-0</b> to <b>-9</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Set the <I>compression level</I>. <b>-0</b> means no compression (store), <b>-9</b> means best compression. Default is <b>-6</b>.<br><br><b><b>-e</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;<I>Encrypt</I> entries in the zip archive using a password. Prompts for a password.<br><br><b><b>-P</b> <I>password</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Use <I>password</I> to encrypt entries. Note: This method is considered insecure.<br><br><b><b>-j</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;<I>Junk paths</I>. Store only the name of the saved file, not its full path.<br><br><b><b>-q</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;<I>Quiet</I> operation. Suppress most messages, only print errors.<br><br><b><b>-v</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;<I>Verbose</I> operation. Print extra information during processing.<br><br><b><b>-x</b> <I>pattern</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Exclude files that match the specified <I>pattern</I> from the archive.<br><br><b><b>-z</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Add a <I>comment</I> to the zip archive. Prompts for the comment text.<br><br>


title: DESCRIPTION
content:
The <b>zip</b> command is a powerful and widely used utility for packaging and compressing files into a single archive, commonly known as a <I>zipfile</I> or <I>.zip</I> archive. It is an open-source counterpart to PKZIP, providing cross-platform compatibility across various operating systems, including Linux, macOS, and Windows.<br><br><I>zip</I> can recursively add directories, compress files, update existing archives, and even delete files from them. It employs the DEFLATE compression method by default, balancing compression ratio and speed, but also supports storing files without compression. While primarily a compression tool, it also serves as an archiving utility by bundling multiple files and their directory structure into a single file, making it convenient for distribution, backup, or simply organizing data.


title: CAVEATS
content:
While <I>zip</I> is excellent for general file compression and archiving, especially for cross-platform compatibility, it has some limitations:<br><I>1. Encryption Security:</I> The built-in password protection (standard ZipCrypto) is known to be weak and can often be cracked. For sensitive data, it's recommended to encrypt files using stronger methods (e.g., GnuPG) <I>before</I> zipping them.<br><I>2. Metadata Preservation:</I> Unlike <I>tar</I>, <I>zip</I> does not preserve all Unix-specific file attributes (like owner, group, full permissions, hard links, symbolic links) robustly across different operating systems. It primarily focuses on file data and directory structure.


title: WILDCARD USAGE
content:
When specifying files, shell wildcards like <I>*</I> (matches any sequence of characters) and <I>?</I> (matches any single character) can be used. It's often crucial to quote these wildcards (e.g., <I>"*.txt"</I>) to prevent the shell from expanding them before <I>zip</I> processes them, ensuring <I>zip</I> itself handles the pattern matching correctly, especially with options like <I>-x</I> (exclude).


title: CROSS-PLATFORM COMPATIBILITY
content:
One of <I>zip</I>'s greatest strengths is its widespread support across different operating systems. A <I>.zip</I> archive created on Linux can generally be easily opened and extracted on Windows or macOS systems, and vice versa, making it an excellent choice for sharing files.


title: HISTORY
content:
The <I>zip</I> file format and its original implementation, PKZIP, were developed by Phil Katz for PKWARE in the late 1980s for MS-DOS. The <I>zip</I> command commonly found on Linux and other Unix-like systems is part of the <B>Info-ZIP</B> project, which began in 1989. Info-ZIP created an open-source, cross-platform compatible suite of utilities (including <I>zip</I> and <I>unzip</I>) that adhered to the <I>zip</I> file format specification, making it a ubiquitous standard for file compression and archiving across diverse computing environments.


title: SYNOPSIS
content:
Although <i>lsdev</i> is not a standard Linux command, its conceptual usage would typically follow a pattern similar to:<br><br><code>lsdev [<I>options</I>] [<I>device_name</I>]</code><br><br>Where <i>options</i> modify the output, and <i>device_name</i> specifies a particular device to query.


title: PARAMETERS
content:
<b>No standard Linux options</b><br>&nbsp;&nbsp;&nbsp;&nbsp;As <i>lsdev</i> is not a standard Linux command, there are no universally defined options. The following parameters are illustrative, based on its functionality in other operating systems or conceptual device listing tools.<br><br><b>-C <I>class</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;<i>(Illustrative)</i> Filter devices by a specific class (e.g., network, disk, storage controller).<br><br><b>-S <I>status</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;<i>(Illustrative)</i> Display devices based on their operational status (e.g., available, defined, detached).<br><br><b>-l <I>logical_name</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;<i>(Illustrative)</i> Show detailed information for a specific logical device name.<br><br><b>-t <I>type</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;<i>(Illustrative)</i> List devices of a particular type (e.g., 'ethernet', 'scsi').<br><br><b>-v</b><br>&nbsp;&nbsp;&nbsp;&nbsp;<i>(Illustrative)</i> Provide more verbose or detailed output about the devices.<br><br>


title: DESCRIPTION
content:
The <i>lsdev</i> command is primarily found on <b>IBM AIX</b> and some System V Unix systems. It is <b>not a standard command</b> on most modern Linux distributions (such as Ubuntu, Fedora, or RHEL), where its functionality is typically provided by other specialized tools.<br><br>Conceptually, <i>lsdev</i> is used to display information about installed hardware devices, including their current status (e.g., 'Available', 'Defined', 'Detached'), configuration, and attributes. It can help system administrators to identify devices, troubleshoot hardware issues, and understand the system's hardware configuration. On Linux, similar information is gathered using commands like <b>lspci</b> for PCI devices, <b>lsusb</b> for USB devices, <b>lshw</b> for comprehensive hardware listings, <b>udevadm</b> for udev device management, and by inspecting the <i>/sys</i> filesystem.


title: CAVEATS
content:
The most significant caveat is that <i>lsdev</i> is <b>not a default or standard command</b> on the vast majority of modern Linux distributions. Users attempting to run it will typically receive a 'command not found' error. Its functionality is specific to other Unix-like operating systems, primarily <b>IBM AIX</b>. On Linux, administrators should use commands like <b>lspci</b>, <b>lsusb</b>, <b>lshw</b>, or <b>udevadm</b> to query hardware information.


title: LINUX EQUIVALENTS
content:
On Linux, there isn't a single command that replicates all the functionality of <i>lsdev</i>. Instead, a combination of tools is used:<br><b>lspci</b>: Lists all PCI devices.<br><b>lsusb</b>: Lists all USB devices.<br><b>lshw</b>: Provides a comprehensive list of all hardware components.<br><b>udevadm</b>: Interacts with the udev device manager, allowing queries about devices managed by udev.<br><b>dmidecode</b>: Reports information about your system's hardware as described in the SMBIOS/DMI.<br>Inspecting <b>/sys</b>: The <i>/sys</i> virtual filesystem contains detailed information about devices and kernel modules.


title: HISTORY
content:
The <i>lsdev</i> command originated in Unix systems, notably becoming a prominent utility within <b>IBM AIX</b> for managing and querying device configurations. Its design reflects a system architecture where devices are managed through a configuration database. While its direct implementation is not prevalent in the Linux kernel or common distributions, the concept of querying system devices has evolved into a suite of specialized utilities on Linux, leveraging the <i>sysfs</i> virtual filesystem and <i>udev</i> for device management.


title: SYNOPSIS
content:
<b>dnf repoquery</b> [<I>options</I>] <I>package-specifier</I>...<br><b>dnf repoquery</b> <B>--queryformat</B> <I>&#x3C;fmt&#x3E;</I> [<I>options</I>] <I>package-specifier</I>...<br><b>dnf repoquery</b> <B>--whatdepends</B> <I>&#x3C;capability&#x3E;</I><br><b>dnf repoquery</b> <B>--whatprovides</B> <I>&#x3C;capability&#x3E;</I>


title: PARAMETERS
content:
<b><B>--all</B></b><br>&nbsp;&nbsp;&nbsp;&nbsp;<i>Query all available versions</i> of packages matching the specifier, rather than just the newest or highest priority.<br><br><b><B>--depends</B></b><br>&nbsp;&nbsp;&nbsp;&nbsp;<i>Display the direct dependencies</i> of the specified packages.<br><br><b><B>--info</B></b><br>&nbsp;&nbsp;&nbsp;&nbsp;<i>Show detailed information</i> about the package, including summary, description, URL, and license.<br><br><b><B>--list</B></b><br>&nbsp;&nbsp;&nbsp;&nbsp;<i>List the files</i> included within the package, as if it were installed.<br><br><b><B>--provides</B></b><br>&nbsp;&nbsp;&nbsp;&nbsp;<i>List the capabilities or virtual packages</i> that the specified package provides.<br><br><b><B>--queryformat=&#x3C;fmt&#x3E;</B></b><br>&nbsp;&nbsp;&nbsp;&nbsp;<i>Specify a custom output format</i> using RPM-style tags for package metadata.<br><br><b><B>--requires</B></b><br>&nbsp;&nbsp;&nbsp;&nbsp;<i>List the capabilities or virtual packages</i> that the specified package requires.<br><br><b><B>--resolve</B></b><br>&nbsp;&nbsp;&nbsp;&nbsp;<i>Recursively resolve and display all dependencies</i> of the specified package, including nested dependencies.<br><br><b><B>--source</B></b><br>&nbsp;&nbsp;&nbsp;&nbsp;<i>Display the name of the source RPM</i> from which the binary package was built.<br><br><b><B>--whatdepends=&#x3C;capability&#x3E;</B></b><br>&nbsp;&nbsp;&nbsp;&nbsp;<i>List packages that have a dependency on the given capability</i> (e.g., a specific file or virtual package).<br><br><b><B>--whatprovides=&#x3C;capability&#x3E;</B></b><br>&nbsp;&nbsp;&nbsp;&nbsp;<i>List packages that provide the given capability</i> (e.g., a specific file or virtual package).<br><br>


title: DESCRIPTION
content:
<i>dnf-repoquery</i> is a powerful plugin for the DNF package manager, designed for querying detailed information about packages available in configured repositories. Unlike <i>rpm -q</i> which queries the RPM database of installed packages, <i>dnf-repoquery</i> fetches information directly from DNF's enabled repositories, allowing users to inspect packages that are not yet installed on the system.<br><br>It's an invaluable tool for system administrators and developers alike, facilitating tasks such as discovering package dependencies (both forward and reverse), identifying which repository provides a specific file or capability, comparing package versions across different repositories, or finding alternative packages. Its querying capabilities extend beyond simple package names, allowing for complex searches based on capabilities, filenames, or specific package attributes.<br><br>By leveraging <i>dnf-repoquery</i>, users can perform comprehensive analyses of the package ecosystem, anticipate dependency conflicts before installation, or troubleshoot issues related to missing or incorrect package versions, making it a critical component of advanced DNF usage. It streamlines the process of gaining insights into the vast amount of metadata managed by DNF.


title: CAVEATS
content:
<i>dnf-repoquery</i> relies on the metadata from enabled repositories. If a repository is out of date or misconfigured, the query results might be inaccurate or incomplete.<br>It performs queries against <i>repository metadata</i>, not against the installed RPM database directly. For information about <i>installed</i> packages, <b>rpm -q</b> or <b>dnf list installed</b> are more appropriate.<br>Extensive use of options like <b>--resolve</b> can be resource-intensive and take time, especially on systems with many enabled repositories or complex dependency trees.<br>Results can vary slightly based on DNF's cache state; a <b>dnf clean all</b> followed by a fresh <b>dnf update</b> might be needed for the most up-to-date metadata.


title: COMMON USE CASES
content:
Beyond basic package information, <i>dnf-repoquery</i> is frequently used for:<br>- <i>Finding packages providing a specific file</i>: <B>dnf repoquery --whatprovides /usr/bin/python3</B><br>- <i>Identifying reverse dependencies</i>: <B>dnf repoquery --whatdepends python3-libs</B><br>- <i>Comparing versions across repositories</i>: <B>dnf repoquery --all &#x3C;package-name&#x3E;</B>


title: EXIT STATUS
content:
The command typically exits with <B>0</B> on success, <B>1</B> if an unhandled error occurs, and <B>100</B> if the command line usage is incorrect.


title: CONFIGURATION
content:
<i>dnf-repoquery</i> honors the DNF configuration files (<B>/etc/dnf/dnf.conf</B> and files in <B>/etc/dnf/plugins/</B>). Repository configurations from <B>/etc/yum.repos.d/</B> are also respected.


title: HISTORY
content:
<i>dnf-repoquery</i> emerged as part of the DNF (Dandified YUM) project, which succeeded YUM (Yellowdog Updater, Modified) as the default package manager for Fedora, CentOS (since 8), and RHEL (since 8). The functionality provided by <i>dnf-repoquery</i> was previously available in <i>yum-utils</i> under the <i>repoquery</i> command. With the transition to DNF, this utility was re-implemented as a native DNF plugin, leveraging DNF's more efficient backend and modular architecture. Its development aimed to provide a faster, more reliable, and feature-rich querying tool that integrates seamlessly with DNF's powerful dependency resolution and repository management capabilities, addressing some of the performance and flexibility limitations observed in the older YUM <i>repoquery</i> utility.


title: SYNOPSIS
content:
<B>i2cdump</B> [<I>-y</I>] [<I>-f</I>] [<I>-r first-last</I>] [<I>-V</I>] [<I>-l</I>] [<I>-u</I>] <I>i2c-bus address</I> [<I>mode</I>]


title: PARAMETERS
content:
<b>i2c-bus</b><br>&nbsp;&nbsp;&nbsp;&nbsp;<I>The I2C bus number or name to scan (e.g., 0, 1, /dev/i2c-0).</I><br><br><b>address</b><br>&nbsp;&nbsp;&nbsp;&nbsp;<I>The 7-bit hexadecimal address of the I2C device on the bus.</I><br><br><b>mode</b><br>&nbsp;&nbsp;&nbsp;&nbsp;<I>The dump mode. Options include:</I><br><B>b</B>: Read individual bytes (default).<br><B>w</B>: Read 16-bit words.<br><B>s</B>: Read SMBus blocks.<br><B>i</B>: Read generic I2C blocks.<br><B>c</B>: Read entire chip memory (potentially dangerous).<br><br><b>-y</b><br>&nbsp;&nbsp;&nbsp;&nbsp;<I>Disable interactive mode. Assume 'yes' for all prompts, which can be dangerous for certain operations.</I><br><br><b>-f</b><br>&nbsp;&nbsp;&nbsp;&nbsp;<I>Force access to the I2C bus. Useful when the kernel thinks another driver is using the bus, but use with caution.</I><br><br><b>-r first-last</b><br>&nbsp;&nbsp;&nbsp;&nbsp;<I>Specify a range of registers to dump (e.g., 0x00-0x1F).</I><br><br><b>-V</b><br>&nbsp;&nbsp;&nbsp;&nbsp;<I>Display the version information and exit.</I><br><br><b>-l</b><br>&nbsp;&nbsp;&nbsp;&nbsp;<I>List all supported dump modes and exit.</I><br><br><b>-u</b><br>&nbsp;&nbsp;&nbsp;&nbsp;<I>Do not print empty lines in the output, making the display more compact.</I><br><br>


title: DESCRIPTION
content:
<I>i2cdump</I> is a powerful command-line utility from the <I>i2c-tools</I> package used for examining the contents of registers on an I2C/SMBus device. It allows users to read and display data directly from an I2C chip's memory or registers at a specified address on a given I2C bus.<br><br>This tool is invaluable for embedded systems developers and hardware engineers for debugging I2C device drivers, verifying hardware functionality, or reverse-engineering unknown I2C devices. It supports various dump modes, including byte-level, word-level, SMBus block reads, and more generic I2C reads, providing flexibility based on the device's communication protocol.<br><br>While highly useful, <I>i2cdump</I> interacts directly with hardware, making it a potentially dangerous tool if misused. Proper care and understanding of the target device's datasheet are essential to avoid unintended side effects or hardware damage.


title: CAVEATS
content:
<B>Hardware Interaction:</B> <I>i2cdump</I> directly interacts with I2C hardware. Incorrect usage, especially with the <I>-f</I> (force) or <I>-c</I> (chip dump) options, can lead to unpredictable device behavior, data corruption, or even permanent hardware damage.<br><br><B>Permissions:</B> Accessing I2C devices typically requires root privileges (e.g., using <I>sudo</I>) to access the <I>/dev/i2c-*</I> devices.<br><br><B>Bus Contention:</B> If other kernel modules or applications are actively using the I2C bus, forcing access with <I>-f</I> can lead to bus contention, potentially disrupting ongoing communications or causing system instability.


title: <B>USAGE EXAMPLES</B>
content:
<I>To dump the first 32 bytes of device at address 0x50 on bus 1 (default byte mode):</I><br><br><CODE>sudo i2cdump 1 0x50</CODE><br><br><I>To dump specific registers (0x10 to 0x1F) in word mode on bus 0, address 0x22:</I><br><br><CODE>sudo i2cdump -r 0x10-0x1F 0 0x22 w</CODE><br><br><I>To list all supported dump modes:</I><br><br><CODE>i2cdump -l</CODE>


title: HISTORY
content:
<I>i2cdump</I> is a core utility within the <I>i2c-tools</I> suite, a collection of userspace programs for communicating with I2C/SMBus devices. Developed initially by Frodo Looijaard and later maintained by Jean Delvare, <I>i2c-tools</I> has been a staple in Linux kernel development and embedded systems debugging for many years. <I>i2cdump</I>'s role has consistently been to provide a low-level view into I2C device registers, evolving with the I2C kernel subsystem to support various bus types and communication modes.


title: TLDR
content:
<b>Dump all registers of an I2C device</b>`i2cdump [i2cbus] [device_address]`<br><b>Dump all registers of an I2C device without asking for confirmation</b>`i2cdump -y [i2cbus] [device_address]`<br><b>Dump all registers of an I2C device using a specific mode</b>`i2cdump [i2cbus] [device_address] [b|w|c|s|i]`<br><b>Dump registers from start to end of an I2C device</b>`i2cdump -r [start]-[end] [i2cbus] [device_address]`


title: PARAMETERS
content:
<b>--nodaemon</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Run once and exit without daemonizing. Useful for testing or one-shot operations.<br><br><b>--check</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Verify the configuration file for syntax and validity, then exit. Does not control fans.<br><br><b>--verbose</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Provide more detailed output during execution, useful for debugging.<br><br><b>--debug</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Output extensive debugging information, typically used by developers.<br><br><b>--config <file></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specify an alternative configuration file path instead of the default (e.g., <i>/etc/fancontrol</i>).<br><br>


title: DESCRIPTION
content:
<i>fancontrol</i> is a daemon that reads temperature data from hardware monitoring chips (via <i>lm-sensors</i>) and adjusts the speed of system fans by controlling their Pulse Width Modulation (PWM) outputs. It's designed to keep your system cool while minimizing fan noise.<br><br>It operates by periodically checking configured temperature sensors and comparing them against user-defined limits (e.g., <i>MINTEMP</i>, <i>MAXTEMP</i>). It dynamically adjusts the fan's PWM value accordingly, increasing speed as temperatures rise and decreasing it when temperatures fall. Proper configuration, often facilitated by <i>pwmconfig</i>, is crucial. It requires a correctly set up <i>lm-sensors</i> installation and root privileges to function effectively.


title: CAVEATS
content:
<ul><li>Requires the <b>lm-sensors</b> package to be installed and a successful run of <b>sensors-detect</b> to identify hardware monitoring chips.</li><li>Needs appropriate kernel modules loaded for specific hardware monitoring chips (e.g., <i>nct6775</i>, <i>it87</i>).</li><li>Requires root privileges to operate, as it directly manipulates hardware registers.</li><li>Configuration can be complex and highly depends on specific motherboard and fan capabilities; <b>pwmconfig</b> is highly recommended for initial setup.</li><li>Incorrect configuration can lead to system overheating or excessive fan noise.</li><li>Not all motherboards or fan headers support PWM control.</li></ul>


title: CONFIGURATION FILE
content:
<i>fancontrol</i> primarily relies on its configuration file, typically located at <i>/etc/fancontrol</i> or <i>/etc/lm-sensors/fancontrol</i>. This file defines which temperature sensors control which PWM outputs, along with crucial parameters such as minimum and maximum temperatures (<i>MINTEMP</i>, <i>MAXTEMP</i>), fan speed ranges (<i>MINPWM</i>, <i>MAXPWM</i>), and the update interval (<i>INTERVAL</i>). It is strongly recommended to generate this file using the <b>pwmconfig</b> utility, which interactively tests fan control capabilities and helps set up the initial configuration based on detected hardware.


title: DAEMON OPERATION
content:
<i>fancontrol</i> is designed to run as a background daemon, ensuring continuous fan speed management. It is usually started automatically at boot via a <i>systemd</i> service (e.g., <i>fancontrol.service</i>) or a traditional <i>init.d</i> script, depending on the Linux distribution's initialization system. Once running, it periodically monitors temperatures and adjusts fan speeds based on the rules defined in its configuration file, providing dynamic thermal management without user intervention.


title: HISTORY
content:
<i>fancontrol</i> is a core component of the <i>lm-sensors</i> project, which began in the late 1990s to provide Linux users with robust hardware monitoring capabilities. Its development has been driven by the increasing need to manage system temperatures and fan acoustics dynamically. It evolved alongside kernel support for various hardware monitoring chips, becoming an essential utility for server and desktop users aiming for optimal system cooling and noise reduction. Its reliance on a configuration file, often generated by the interactive <i>pwmconfig</i> utility, has been a consistent aspect of its design, simplifying the initial setup process for most users.


title: TLDR
content:
<b>Start fancontrol using default /etc/fancontrol configuration file</b>`fancontrol`<br><b>Start fancontrol using custom configuration file path</b>`fancontrol [path/to/config_file]`


title: SYNOPSIS
content:
<b>i2cdetect</b> [<i>OPTIONS</i>] <i>BUS</i><br><b>i2cdetect</b> <i>-l</i><br><b>i2cdetect</b> <i>-F BUS</i>


title: PARAMETERS
content:
<b>-y</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Assume yes to all queries. Prevents interactive prompts, useful for scripting.<br><br><b>-r</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Read-only mode. Performs a scan without writing to the I2C bus, making it safer for production systems.<br><br><b>-a LOW HIGH</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Scan a specific address range from LOW to HIGH (inclusive, in hexadecimal).<br><br><b>-q</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Quick mode. Reduces the number of probes for faster detection, but might be less reliable.<br><br><b>-F</b><br>&nbsp;&nbsp;&nbsp;&nbsp;List the capabilities and features of the specified I2C bus, such as supported protocols and functions.<br><br><b>-l</b><br>&nbsp;&nbsp;&nbsp;&nbsp;List all detected I2C buses on the system, showing their bus numbers and descriptions.<br><br><b>-V</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Display the version information of the <i>i2cdetect</i> command.<br><br><b>-d</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Enable debug output, providing more verbose information during execution for troubleshooting.<br><br><b>-I ADDRS</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Ignore specified I2C addresses (comma-separated list) during the scan, preventing probes to known problematic devices.<br><br>


title: DESCRIPTION
content:
The <i>i2cdetect</i> command is a powerful utility within the <i>i2c-tools</i> package, designed to scan an I2C bus for connected devices and report their corresponding hexadecimal addresses. It's an essential tool for embedded systems development, hardware debugging, and verifying device presence on an I2C bus. <br><br>Users can specify the I2C bus number to scan, or list all available buses. The command offers various modes, including a safe read-only mode (<i>-r</i>) to prevent accidental writes, and options to scan specific address ranges. Its output typically displays a matrix of I2C addresses, marking detected devices, addresses in use by kernel modules (UU), or empty slots (--). It requires root privileges to operate, as it directly interacts with low-level hardware. Caution is advised, especially when not using the read-only flag, as probing certain addresses can potentially interfere with active devices.


title: CAVEATS
content:
Requires root privileges (or <i>sudo</i>) to access I2C bus devices. <br>Probing addresses without the <i>-r</i> (read-only) flag can potentially interfere with or disrupt actively communicating I2C devices. <br>Addresses marked as <i>UU</i> indicate that a kernel module is already using that address, and <i>i2cdetect</i> will not probe it. <br>Some I2C devices may not respond correctly to the general call address probe, or may respond in unexpected ways.


title: OUTPUT FORMAT
content:
The output is typically a grid where rows represent the higher nibble and columns represent the lower nibble of the I2C address. <br><i>--</i> indicates no device found at that address. <br><i>UU</i> indicates the address is in use by a kernel driver. <br><i>XX</i> may indicate a conflict or multiple devices. <br>A two-digit hexadecimal number (e.g., <i>48</i>) indicates a device was detected at that address.


title: BUS NUMBER
content:
The <i>BUS</i> argument typically corresponds to <i>/dev/i2c-N</i>, where <i>N</i> is the bus number. You can use <i>i2cdetect -l</i> to list available buses and their corresponding device paths.


title: HISTORY
content:
<i>i2cdetect</i> is part of the <i>i2c-tools</i> package, a suite of utilities for communicating with I2C/SMBus devices. The package and its tools have been developed over many years to provide essential user-space access to I2C buses on Linux systems, evolving with kernel I2C subsystem changes to support a wide range of hardware platforms.


title: TLDR
content:
<b>List active I2C buses</b>`i2cdetect -l`<br><b>Scan devices on an I2C bus</b>`i2cdetect [i2c_bus]`<br><b>Scan devices on an I2C bus without asking for confirmation</b>`i2cdetect -y [i2c_bus]`


title: TLDR
content:
<b>Write to a register of an I2C device</b>`i2cset [i2cbus] [device_address] [register_address] [value]`<br><b>Write to a register of an I2C device without asking for confirmation</b>`i2cset -y [i2cbus] [device_address] [register_address] [value]`<br><b>Write to a register of an I2C device using a specific mode</b>`i2cset [i2cbus] [device_address] [register_address] [value] [b|w|c|s|i]`


title: SYNOPSIS
content:
<b>dnf module</b> [<i>options</i>] <i>&lt;command&gt;</i><br><i>&lt;command&gt;</i> can be one of: <b>list</b>, <b>enable</b>, <b>disable</b>, <b>install</b>, <b>remove</b>, <b>info</b>, <b>reset</b>, <b>update</b>, <b>provides</b>.<br><br>Common usage examples:<br><b>dnf module list</b> [<i>module</i>] [<i>options</i>]<br><b>dnf module enable</b> <i>module</i>:<i>stream</i> [...]<br><b>dnf module install</b> <i>module</i>[:<i>stream</i>[:<i>profile</i>]] [...]<br><b>dnf module disable</b> <i>module</i> [...]<br><b>dnf module reset</b> <i>module</i> [...]


title: PARAMETERS
content:
<b>list</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Lists available modules, their streams, and profiles. Can be filtered by module name or options like <b>--enabled</b>.<br><br><b>enable <i>&lt;module&gt;</i>:<i>&lt;stream&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Enables a specific module stream. This makes packages from that stream available for installation and disables any conflicting streams.<br><br><b>disable <i>&lt;module&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Disables a module, making its packages unavailable. This does not remove already installed packages but prevents further installation from that module.<br><br><b>install <i>&lt;module&gt;</i>[:<i>&lt;stream&gt;</i>[:<i>&lt;profile&gt;</i>]]</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Installs packages defined by a module profile. If no profile is specified, the 'default' profile is often used. If no stream, the default enabled stream is used.<br><br><b>remove <i>&lt;module&gt;</i>[:<i>&lt;stream&gt;</i>[:<i>&lt;profile&gt;</i>]]</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Removes packages previously installed as part of a module profile. Use with caution as it can remove dependencies.<br><br><b>info [<i>&lt;module&gt;</i>[:<i>&lt;stream&gt;</i>[:<i>&lt;profile&gt;</i>]]]</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays detailed information about specified modules, streams, or profiles, including descriptions and package lists.<br><br><b>reset <i>&lt;module&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Resets the module's state to its default. This typically disables the module and makes its default stream available again.<br><br><b>update [<i>&lt;module&gt;</i>[:<i>&lt;stream&gt;</i>]]</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Updates packages within enabled module streams. Can be used to update all or specific modules.<br><br><b>provides <i>&lt;what&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Searches which module provides a specific package or capability.<br><br><b>--all</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Used with 'list' to show all modules, including enabled, disabled, installed, and available ones.<br><br><b>--enabled</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Used with 'list' to show only enabled module streams.<br><br><b>--disabled</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Used with 'list' to show only disabled module streams.<br><br><b>--installed</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Used with 'list' to show only installed module streams and profiles.<br><br><b>--available</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Used with 'list' to show only available module streams.<br><br><b>--stream <i>&lt;stream_name&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Filters module operations by a specific stream name.<br><br><b>--profile <i>&lt;profile_name&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies a module profile for 'install' or 'remove' operations.<br><br>


title: DESCRIPTION
content:
<b>dnf-module</b> is a powerful subcommand of the DNF package manager, designed for managing software modules. Modules encapsulate software components and their dependencies, offering different <i>streams</i> (versions or release lines) and <i>profiles</i> (curated sets of packages for specific use cases) of applications. This command allows users to discover, enable, disable, install, and manage these module-defined software stacks. It addresses challenges like dependency conflicts and provides a more controlled, stable, and flexible way to consume software than traditional package management alone, especially for applications with rapid development cycles or multiple maintained versions. It's crucial for maintaining consistent and predictable application environments on systems like Fedora and Red Hat Enterprise Linux.


title: CAVEATS
content:
Module operations can significantly alter the available software stack on your system.<br>Enabling a module stream might automatically disable other conflicting streams of the same module, which could impact existing applications.<br>Most <b>dnf module</b> commands require root privileges.<br>Careful consideration of streams and profiles is essential to avoid unexpected package conflicts or software behavior.


title: MODULE STREAMS
content:
A <i>module stream</i> represents a specific version or release line of a software component (e.g., <b>nodejs:16</b>, <b>nodejs:18</b>). Enabling a stream makes packages from that specific version available for installation. Only one stream of a given module can be enabled at a time.


title: MODULE PROFILES
content:
A <i>module profile</i> is a curated set of packages within a specific module stream, tailored for a particular use case (e.g., <b>nodejs/default</b>, <b>nodejs/development</b>, <b>nodejs/minimal</b>). Profiles simplify the installation of complex applications by grouping necessary dependencies and tools together.


title: HISTORY
content:
The concept of modules was introduced with <b>DNF</b> version 2 and <b>YUM</b> version 4, becoming a cornerstone feature in Red Hat Enterprise Linux 8 and Fedora 28 onwards. This innovation aimed to provide greater flexibility in managing software lifecycles and dependencies, allowing multiple versions of applications (e.g., Python, Node.js) to coexist or be managed independently on the same system. The <b>dnf-module</b> subcommand specifically provides the interface to interact with this modularity framework, evolving from initial <b>dnf module</b> experimental commands to a stable and essential part of DNF's capabilities.


title: TLDR
content:
<b>View the modularity overview</b>`dnf module list`<br><b>View modularity of a specific program</b>`dnf module list [package_name]`<br><b>Set a package to be enabled</b>`sudo dnf module enable [package_name]:[stream]`<br><b>Enable and install a specific version</b>`dnf module install [package_name]:[stream]`


title: PARAMETERS
content:
<b>--destdir=&lt;directory&gt;</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specify the destination directory for downloaded packages.<br><br><b>--source</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Download the source RPM (SRPM) for the specified package.<br><br><b>--resolve</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Resolve and download all necessary package dependencies.<br><br><b>--url</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Instead of downloading, print the direct download URL for the package.<br><br><b>--urls</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Print all download URLs for the package and its dependencies.<br><br><b>--enablerepo=&lt;repo_id&gt;</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Enable specific repositories by their ID for the download operation.<br><br><b>--disablerepo=&lt;repo_id&gt;</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Disable specific repositories by their ID for the download operation.<br><br><b>-y, --assumeyes</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Automatically answer yes to all prompts during the download process.<br><br><b>--debuginfo</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Download corresponding debuginfo packages for the specified RPMs.<br><br><b>--nogpgcheck</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Disable GPG signature checking for downloaded packages.<br><br><b>--latest</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Download only the latest version of the specified package.<br><br><b>--archlist=&lt;arch1,arch2,...&gt;</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Limit packages to be downloaded to a specific list of architectures.<br><br>


title: DESCRIPTION
content:
<i><b>yumdownloader</b></i> is a specialized utility that allows users to download RPM packages directly from Yum repositories without performing an installation on the system. This capability is invaluable for various administrative tasks, such as creating local mirrors of repositories, preparing packages for offline deployments in isolated networks, or inspecting package contents before commitment to a live system.<br><br>It supports resolving and downloading package dependencies, fetching source RPMs, and specifying a target directory for the downloaded files. While the broader <i>yum</i> ecosystem has been largely superseded by <i>dnf</i> in modern Red Hat-based distributions, <i><b>yumdownloader</b></i> remains relevant for managing legacy systems or in environments where <i>yum</i> is still the primary package manager.


title: CAVEATS
content:
<i><b>yumdownloader</b></i> is part of the <i>yum</i> ecosystem, which has been largely deprecated in favor of <i>dnf</i> on modern Red Hat-based distributions (e.g., Fedora 22+, RHEL 8+). Users on newer systems should prefer <i><b>dnf download</b></i> for similar functionality. This command only downloads packages; it does not perform installation or dependency resolution against the local system's installed packages.


title: USAGE EXAMPLE
content:
To download the 'httpd' package along with all its required dependencies into a specific directory, such as '/tmp/offline_rpms':<br><br><b>yumdownloader</b> --resolve --destdir=/tmp/offline_rpms httpd<br><br>This command will fetch the 'httpd' RPM and any packages it depends on into the '/tmp/offline_rpms' directory. This set of packages can then be used for offline installation or for building a local repository.


title: HISTORY
content:
<i><b>yumdownloader</b></i> originated as a component of the <i>yum</i> (Yellowdog Updater, Modified) package manager, which became the standard package management tool for Red Hat Enterprise Linux and its derivatives for many years. It was developed to provide granular control over package retrieval, allowing administrators to prepare systems offline or manage custom repositories. With the advent of <i>dnf</i> (Dandified Yum), which offers improved dependency resolution and performance, <i><b>dnf download</b></i> has succeeded <i><b>yumdownloader</b></i> as the preferred tool on newer systems, though <i><b>yumdownloader</b></i> remains available and functional on systems still utilizing <i>yum</i>.


title: TLDR
content:
<b>Install packages by name</b>`sudo dnf [[in|install]] [package1 package2 ...]`<br><b>Install a package from a local file</b>`sudo dnf [[in|install]] [path/to/file]`<br><b>Install a package from the internet</b>`sudo dnf [[in|install]] [https://example.com/package.rpm]`<br><b>Add the Extra Packages for Enterprise Linux (EPEL) repositories</b>`sudo dnf [[in|install]] https://dl.fedoraproject.org/pub/epel/epel-release-latest-[10].noarch.rpm`<br><b>Add Remi's RPM repository</b>`sudo dnf [[in|install]] https://rpms.remirepo.net/enterprise/remi-release-[8].rpm`


title: SYNOPSIS
content:
<B>i2cget</B> [<I>-y</I>|<I>-f</I>] [<I>-V</I>] [<I>-q</I>] <I>I2CBUS</I> <I>CHIP-ADDRESS</I> [<I>DATA-ADDRESS</I> [<I>MODE</I>]]


title: PARAMETERS
content:
<b><I>I2CBUS</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;The number of the <B>I2C</B> bus to communicate with (e.g., 0, 1). This typically corresponds to <I>/dev/i2c-N</I>.<br><br><b><I>CHIP-ADDRESS</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;The 7-bit hexadecimal address of the <B>I2C</B> device on the specified bus (e.g., <I>0x50</I>). This is a required argument.<br><br><b><I>DATA-ADDRESS</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Optional. The hexadecimal address of the register or memory location within the chip to read from (e.g., <I>0x00</I>). If omitted, a direct byte read (<I>c</I> mode) is performed.<br><br><b><I>MODE</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Optional. Specifies the read mode. Common modes include:<br>  <B>b</B>: Read a single byte from <I>DATA-ADDRESS</I>. (Default if <I>DATA-ADDRESS</I> is provided)<br>  <B>w</B>: Read a 16-bit word (two bytes) from <I>DATA-ADDRESS</I>.<br>  <B>c</B>: Read a single byte directly from the device (no <I>DATA-ADDRESS</I> is sent). (Default if <I>DATA-ADDRESS</I> is omitted)<br>  <B>B</B>: Perform an <B>SMBus</B> block read, returning up to 32 bytes.<br><br><b><I>-y</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Disable interactive mode. Assumes 'yes' to all prompts, useful for scripting.<br><br><b><I>-f</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Force access to the <B>I2C</B> bus, even if it is busy. Use with extreme caution as it can cause bus conflicts or data corruption.<br><br><b><I>-V</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Display the version number of <B>i2cget</B> and exit.<br><br><b><I>-q</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Quiet mode. Suppress standard output, useful when only the exit status matters.<br><br>


title: DESCRIPTION
content:
<B>i2cget</B> is a utility from the <B>i2c-tools</B> package designed to read data from <B>I2C</B> or <B>SMBus</B> client devices connected to an <B>I2C</B> bus. It provides a simple command-line interface for low-level interaction with these devices. Users specify the <B>I2C</B> bus number, the 7-bit chip address of the target device, and optionally a data address (register) within the device to read from. The command supports various read modes including a single byte read, a word read (two bytes), or a block read, depending on the device's capabilities and the desired interaction.<br><br>This tool is invaluable for debugging <B>I2C</B> device drivers, verifying hardware connectivity, and directly manipulating device registers during development or system bring-up. It acts as a direct interface to the <B>I2C</B> kernel driver, translating command-line arguments into <B>I2C</B> bus transactions. It's commonly used to read sensor data, <B>EEPROM</B> contents, or status registers.


title: CAVEATS
content:
Using <B>i2cget</B> typically requires root privileges (e.g., <B>sudo</B>) to access the <B>I2C</B> device files. Improper use of <I>CHIP-ADDRESS</I>, <I>DATA-ADDRESS</I>, or <I>MODE</I> can lead to incorrect readings, bus hangs, or even damage to <B>I2C</B> devices. The <B>i2c-dev</B> kernel module must be loaded for <B>i2cget</B> to function correctly. The <I>-f</I> (force) option should be used with extreme caution, as it bypasses safety checks and can interfere with other processes or hardware on the bus.


title: PERMISSIONS
content:
Due to direct hardware access to <I>/dev/i2c-*</I> devices, <B>i2cget</B> usually requires superuser (root) privileges. It's common to prefix the command with <B>sudo</B>.


title: BUS CONFLICTS AND SAFETY
content:
If other processes or kernel drivers are actively using the <B>I2C</B> bus, <B>i2cget</B> might fail or cause conflicts. The <I>-f</I> option can bypass some safety checks, but it increases the risk of system instability or corrupting ongoing <B>I2C</B> transactions.


title: ADDRESS FORMAT
content:
Both <I>CHIP-ADDRESS</I> and <I>DATA-ADDRESS</I> are typically specified in hexadecimal format. You can use the <I>0x</I> prefix (e.g., <I>0x50</I>) or simply provide the hexadecimal value (e.g., <I>50</I>).


title: HISTORY
content:
<B>i2cget</B> is part of the <B>i2c-tools</B> project, an open-source collection of utilities developed to provide command-line interaction with <B>I2C</B> and <B>SMBus</B> devices on Linux. Its development has closely tracked the evolution of the Linux kernel's <B>I2C</B> subsystem, making it an essential tool for developers and engineers working with embedded systems and hardware interfacing. It has been a staple in the <B>i2c-tools</B> suite for many years.


title: TLDR
content:
<b>Read from a register of an I2C device</b>`i2cget [i2cbus] [device_address] [register_address]`<br><b>Read from a register of an I2C device without asking for confirmation</b>`i2cget -y [i2cbus] [device_address] [register_address]`<br><b>Read from a register of an I2C device using a specific mode</b>`i2cget [i2cbus] [device_address] [register_address] [b|w|c|s|i]`


title: TLDR
content:
<b>Lock current virtual console session</b>`vlock`<br><b>Lock current virtual console session via flag</b>`vlock [[-c|--current]]`<br><b>Lock all virtual console sessions</b>`vlock [[-a|--all]]`<br><b>Display help</b>`vlock [[-h|--help]]`<br><b>Display version</b>`vlock [[-v|--version]]`


title: PARAMETERS
content:
<b><code>-fullscreen</code></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Launches the game in <b>fullscreen</b> display mode.<br><br><b><code>-windowed</code></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Launches the game in a <b>windowed</b> display mode.<br><br><b><code>-console</code></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Enables the in-game developer <b>console</b> immediately upon launch.<br><br><b><code>-novid</code></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Skips the Valve intro movie at startup.<br><br><b><code>+<I>cvar</I> <I>value</I></code></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets a specific <b>console variable</b> (cvar) or executes a command, e.g., <br><code>+cl_showfps 1</code>.<br><br><b><code>-exec <I>file</I></code></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Executes commands from the specified <b>configuration file</b> (e.g., autoexec.cfg) at startup.<br><br>


title: DESCRIPTION
content:
The <code>cs2</code> command on Linux typically refers to the executable or a wrapper script used to launch the popular first-person shooter game, <I>Counter-Strike 2</I>. While not a standard system utility found in most distributions, <code>cs2</code> is the common identifier for the game's client executable. Users commonly interact with it indirectly through the Steam client, which manages game installation, updates, and provides a graphical interface for launch options. However, for advanced users or scripting purposes, <code>cs2</code> can be invoked directly from the command line, often residing within Steam's game library directory. Direct execution allows for custom launch parameters, enabling specific configurations like resolution, refresh rate, console activation, or debugging modes without modifying in-game settings. This provides flexibility for competitive players or those troubleshooting issues.


title: CAVEATS
content:
The <I>cs2</I> command is <b>not a standard Linux system utility</b>. Its presence and behavior depend entirely on the installation of the <I>Counter-Strike 2</I> game, typically managed by the Steam client. Direct invocation may require navigating to the game's installation directory or ensuring the game's executable path is added to the system's PATH. Compatibility and performance on Linux are often influenced by Steam's Proton compatibility layer, which translates Windows API calls to Linux equivalents, and graphics drivers. Command-line options can vary with game updates.


title: CONFIGURATION FILES
content:
Many game settings are stored in <b>.cfg</b> files (e.g., config.cfg, autoexec.cfg) within the game's directory. These can be edited manually or executed via the <code>-exec</code> launch option.


title: IN-GAME CONSOLE
content:
The developer console, enabled with the <code>-console</code> launch option or by pressing the <b>tilde (~) key</b>, allows for direct input of commands and console variables (cvars) during gameplay.


title: HISTORY
content:
<I>Counter-Strike 2</I> is the successor to <I>Counter-Strike: Global Offensive</I> (CS:GO), which itself evolved from earlier versions like <I>Counter-Strike 1.6</I> and <I>Counter-Strike: Source</I>. CS2 was officially released in September 2023, replacing CS:GO. It brought significant updates to the Source 2 engine, improving graphics, lighting, and gameplay mechanics, including "sub-tick" updates. The transition was controversial for some players due to changes in gameplay feel and the removal of certain CS:GO features. On Linux, CS2, like CS:GO, relies heavily on Valve's Steam client and the Proton compatibility layer for optimal performance and functionality, as native Linux client development is not prioritized for this game.


title: SYNOPSIS
content:
<i><b>aide</b> [<b>-C</b>] [<b>-c</b> <I>config_file</I>] [<b>-D</b> <I>debug_level</I>] [<b>-h</b>] [<b>-i</b>] [<b>-r</b> <I>report_file</I>] [<b>-s</b>] [<b>-u</b>] [<b>-V</b>] [<b>-v</b>] [<b>--before-init</b>=<I>file</I>] [<b>--after-check</b>=<I>file</I>] [<b>--limit-cpu</b>=<I>limit</I>] [<b>--url</b>=<I>url</I>]</i>


title: PARAMETERS
content:
<b>-c <I>config_file</I>, --config=<I>config_file</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the path to the configuration file. By default, <I>AIDE</I> looks for <I>/etc/aide/aide.conf</I> or <I>/etc/aide.conf</I>.<br><br><b>-C, --check</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Checks the integrity of files against the database. This is the default action if no command-line option is specified.<br><br><b>-i, --init</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Initializes the <I>AIDE</I> database. This creates a baseline snapshot of your system's files and their attributes. It should be run on a clean, trusted system.<br><br><b>-u, --update</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Updates the <I>AIDE</I> database. This mode is used after legitimate system changes (e.g., software updates) to create a new database that incorporates these changes, effectively creating a new baseline.<br><br><b>-h, --help</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays a brief help message with available options.<br><br><b>-V, --version</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Shows the <I>AIDE</I> version information and compilation options.<br><br><b>-v, --verbose</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Increases the verbosity of the output. Can be specified multiple times for more detailed messages.<br><br><b>-D <I>debug_level</I>, --debug=<I>debug_level</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets the debug level for troubleshooting. Higher numbers provide more detailed debug information.<br><br><b>-r <I>report_file</I>, --report=<I>report_file</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Writes the integrity check report to the specified file instead of standard output.<br><br><b>-s, --strict</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Enables strict checking of the configuration file, exiting if any warnings are encountered.<br><br><b>--limit-cpu=<I>limit</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Limits the CPU usage percentage <I>AIDE</I> can consume during its operation.<br><br><b>--before-init=<I>file</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Executes the specified script or command before the database initialization (<I>aide -i</I>) begins.<br><br><b>--after-check=<I>file</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Executes the specified script or command after the integrity check (<I>aide -C</I>) completes.<br><br><b>--url=<I>url</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Allows specifying a configuration file via a URL (e.g., <I>file://</I>, <I>http://</I>), useful for remote configuration management.<br><br>


title: DESCRIPTION
content:
<i><I>AIDE</I> (Advanced Intrusion Detection Environment) is a powerful and versatile file and directory integrity checker for Unix-like operating systems. It is primarily used as a proactive security measure to detect unauthorized modifications to system files and binaries, which could indicate a compromise, malware infection, or accidental changes. <br><br> <I>AIDE</I> works by creating a cryptographic hash database (a "snapshot") of selected files and directories on the system. This database stores various attributes like checksums (MD5, SHA256, etc.), file permissions, ownership, inode number, and modification times. Once the baseline database is established, subsequent runs of <I>AIDE</I> compare the current state of the files against this stored baseline. Any discrepancies – new files, deleted files, or modified attributes – are reported, alerting administrators to potential security incidents. Its flexibility lies in its highly configurable rules, allowing users to specify exactly which files to monitor and what attributes to track, making it an essential tool for maintaining system integrity and compliance.</i>


title: CAVEATS
content:
<i><I>AIDE</I> is a powerful tool, but its effectiveness relies on several factors:<br><br><b>Baseline Integrity:</b> The initial database must be created on a system that is known to be clean and uncompromised. If the baseline is infected, <I>AIDE</I> will fail to detect existing threats.<br><b>Database Security:</b> The <I>AIDE</I> database file is critical. It should be stored on read-only media, on a separate secure system, or at least in a location not easily accessible or modifiable by an attacker.<br><b>False Positives:</b> Legitimate system changes (e.g., software updates, log file rotations, temporary file creations) can trigger alerts. Proper configuration of rules to ignore expected changes is crucial to minimize noise.<br><b>Performance Overhead:</b> On very large file systems, especially with deep directory structures and many files, <I>AIDE</I> scans can be resource-intensive and time-consuming. Careful configuration of what to monitor can mitigate this.<br><b>Detection Scope:</b> <I>AIDE</I> detects changes to files. It cannot detect zero-day exploits that don't modify files or sophisticated rootkits that operate solely in memory and actively hide their presence from the filesystem. It should be part of a layered security strategy.</i>


title: CONFIGURATION FILE (<I>AIDE.CONF</I>)
content:
<i>The behavior of <I>AIDE</I> is entirely controlled by its configuration file, typically located at <I>/etc/aide/aide.conf</I> or <I>/etc/aide.conf</I>. This file defines:<br><b>Databases:</b> Paths to the input and output database files.<br><b>Rules:</b> Which files and directories to monitor, and which attributes (e.g., permissions, inode, number of links, user, group, size, mtime, atime, ctime, checksums) to check for each.<br><b>Exclusions:</b> Paths to ignore (e.g., temporary files, log files that change frequently).<br>The file uses a simple syntax with rules specified using regular expressions and predefined attribute sets (e.g., <I>R</I> for regular file attributes, <I>P</I> for permissions, <I>L</I> for links, <I>E</I> for entire file, <I>MD5</I>, <I>SHA256</I> for checksums). Proper configuration is crucial for effective monitoring and minimizing false positives.</i>


title: MODES OF OPERATION
content:
<i><I>AIDE</I> primarily operates in three distinct modes:<br><b>Initialize (<I>aide -i</I>):</b> Creates the initial integrity database. This is a crucial step and should be performed only after ensuring the system is in a known good state.<br><b>Check (<I>aide -C</I>):</b> Compares the current state of files against the stored database, reporting any discrepancies. This is the primary mode for detecting unauthorized changes.<br><b>Update (<I>aide -u</I>):</b> Generates a new database based on the current system state, but only after performing a check against the old database. It's typically used after legitimate system modifications (e.g., OS updates) to establish a new baseline, ensuring that only expected changes are incorporated into the new database.</i>


title: HISTORY
content:
<i><I>AIDE</I> was designed as a free, open-source alternative to proprietary file integrity monitoring tools like <I>Tripwire</I>. Development began in the late 1990s, with its initial public release occurring around 1999. It quickly gained popularity due to its flexibility, comprehensive features, and open-source nature, allowing for community contributions and audits. Over the years, it has undergone continuous development, adding support for more hashing algorithms (like SHA256, SHA512), improved configuration options, and better performance, making it a robust and widely adopted tool for system integrity monitoring in various Linux and Unix-like environments. Its design emphasizes security through cryptographic integrity checks and a highly configurable rule-based system.</i>


title: TLDR
content:
<b>Initialize the database</b>`sudo aide [[-i|--init]]`<br><b>Check the database for inconsistencies</b>`sudo aide [[-C|--check]]`<br><b>Compare two databases according to definitions in the config file</b>`sudo aide [[-E|--compare]]`<br><b>Check and update the database non-interactively</b>`sudo aide [[-u|--update]]`<br><b>Define a config file to override the default ./aide.conf</b>`sudo aide [[-c|--config]] [path/to/config_file]`<br><b>Use regex to limit AIDE to a specific string</b>`sudo aide [[-l|--limit]] [regex]`<br><b>Send reporter results to a URL</b>`sudo aide [[-r|--report]] [reporterurl]`


title: TLDR
content:
<b>Open a new Ptyxis window</b>`ptyxis --new-window`<br><b>Execute a specific command in a new terminal window</b>`ptyxis [[-x|--execute]] [command]`<br><b>Open new tab in the last opened window</b>`ptyxis --tab`<br><b>Set the title for a new</b>`ptyxis --tab [[-T|--title]] [title]`<br><b>Specify the working directory for a new tab, window, or command execution</b>`ptyxis [[-d|--working-directory]] [path/to/directory] --tab`


title: DESCRIPTION
content:
The command <b>fftest</b> is not a standard utility found in common Linux distributions such as Debian, Ubuntu, Fedora, or Arch Linux. It is not part of coreutils, util-linux, or other widely adopted software packages.<br><br>When a command is not standard, it typically means one of several things:<br>1. It might be a <i>typo</i> for a similar-sounding command (e.g., <I>ffmpeg</I>, <I>ffplay</I>, or even <I>ffftest</I> which relates to Free Fall testing in some hardware contexts).<br>2. It could be a <i>custom script</i> or executable developed for a very specific environment, project, or hardware setup.<br>3. It might belong to a highly specialized or niche software package that is not commonly installed or distributed.<br>4. It may be an internal debugging or testing tool within a specific application's source code, not intended for general user execution.<br><br>Without additional context regarding its origin or the specific software it might be associated with, it is impossible to provide accurate details on its functionality, usage, or parameters.


title: CAVEATS
content:
This command name is not listed in standard Linux manual pages or package repositories. Any usage or documentation found would likely be specific to a custom or very niche environment. It is crucial to verify the command's source before attempting to execute it, especially if encountered in an unfamiliar context.


title: CLARIFICATION NEEDED
content:
If you encountered <b>fftest</b> in a particular scenario, providing more context (e.g., the software package, specific hardware, or source code where it appeared) would be necessary for a precise analysis.


title: HISTORY
content:
As <b>fftest</b> is not a standard Linux command, there is no public development history or widely recognized usage pattern associated with it.


title: PARAMETERS
content:
<b><b>--repoid=</b><I>repoid</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specify a repository ID to include or exclude packages from when searching for changelogs.<br><br><b><b>--all</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Display changelogs for all installed and all available packages.<br><br><b><b>--available</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Show changelogs only for available (not necessarily installed) packages.<br><br><b><b>--installed</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Show changelogs only for installed packages. This is the default behavior if no <I>package-spec</I> is provided.<br><br><b><b>--count=</b><I>number</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Limit the number of changelog entries displayed per package to the specified <I>number</I>.<br><br><b><b>--xml</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Output the changelog information in XML format, which is useful for machine parsing.<br><br>


title: DESCRIPTION
content:
The <b>dnf-changelog</b> command is a plugin for the <I>DNF</I> package manager, designed to retrieve and display the changelog entries for installed or available packages. A changelog provides a historical record of modifications, bug fixes, and new features implemented in a package over time. This functionality is crucial for users needing to understand a package's evolution, troubleshoot issues, or verify specific changes. By default, if no specific package is named, <b>dnf-changelog</b> lists changelogs for all currently installed packages. Users can refine their search by specifying package names, filtering by repository ID, limiting the number of entries, or choosing to view changelogs for only available or all packages. The command also supports outputting the changelog in an XML format for easier programmatic processing.


title: CAVEATS
content:
The accuracy and detail of changelog entries depend on the information provided within the RPM packages themselves. Not all packages may contain comprehensive changelogs, or they might follow varying formats. Querying changelogs for a very large number of packages without specific filters can be resource-intensive and slow.


title: EXIT STATUS
content:
The command typically returns an exit status of <b>0</b> on success, and a non-zero value (usually <b>1</b>) if an error occurs during execution, such as an invalid option or a failure to retrieve changelog data.


title: HISTORY
content:
<b>dnf-changelog</b> is part of the <b>dnf-plugins-core</b> package, extending the functionality of the DNF package manager. It provides a modern equivalent to similar changelog capabilities found in the older YUM ecosystem, adapting to DNF's plugin architecture to offer robust package history viewing.


title: TLDR
content:
<b>View all changelogs for a given package</b>`dnf changelog [package]`<br><b>View all changelogs for a given package after a specified date</b>`dnf changelog --since [date] [package]`<br><b>View the last n number of changelogs for a given package</b>`dnf changelog --count [number] [package]`<br><b>Show only new items for upgradeable packages</b>`dnf changelog --upgrades [package]`<br><b>Display help</b>`dnf changelog --help-cmd`


title: PARAMETERS
content:
<b>package-specifier</b><br>&nbsp;&nbsp;&nbsp;&nbsp;<I>Required.</I> The name or glob pattern of the package(s) for which to list dependencies. Examples: <I>httpd</I>, <I>kernel\*</I>.<br><br><b>--all</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Show all types of dependencies (requires, recommends, suggests, enhances, supplements, conflicts, obsoletes, provides). By default, only runtime requirements are shown.<br><br><b>--arch <ARCH></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Filter dependencies by a specific architecture, such as <I>x86_64</I> or <I>i686</I>.<br><br><b>--conflicts</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Show packages that conflict with the specified package.<br><br><b>--enhances</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Show packages that this package enhances.<br><br><b>--obsoletes</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Show packages that this package obsoletes.<br><br><b>--provides</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Show what capabilities the package itself provides (not its dependencies). Useful for seeing what virtual provides a package offers.<br><br><b>--recommends</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Show recommended packages. These are not strictly required but provide enhanced functionality.<br><br><b>--repo <REPONAME></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Limit the dependency search to a specific repository ID. Can be used multiple times. Example: <I>--repo epel --repo updates</I>.<br><br><b>--requires</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Show required packages. This is the default behavior if no other dependency type option is specified.<br><br><b>--srpm</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Show dependencies of the source RPM (SRPM) for the specified package. Useful for build environments.<br><br><b>--suggests</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Show suggested packages. These are even weaker dependencies than recommendations.<br><br><b>--supplements</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Show packages that supplement this package.<br><br><b>--verbose</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Provide more detailed output, including full N-E-V-R-A (Name-Epoch-Version-Release-Architecture) of packages and more explicit dependency types.<br><br>


title: DESCRIPTION
content:
The `dnf-deplist` command is a powerful utility within the DNF package manager ecosystem, designed to provide comprehensive information about the dependencies of specified RPM packages. It queries the enabled DNF repositories to identify not just direct requirements but also indirect dependencies, conflicts, and other related package relationships. This tool is invaluable for system administrators, developers, and users who need to understand why a particular package is needed, what other packages it relies upon, or what capabilities it provides.<br><br>Unlike `rpm -qR`, which only shows direct runtime requirements from the RPM header, `dnf-deplist` performs a deeper analysis using the DNF solver, taking into account the available packages in your configured repositories. It can show different types of dependencies, such as runtime requirements, build requirements, weak dependencies (like recommendations and suggestions), and even packages that conflict or are obsoleted. Its output helps in troubleshooting installation issues, building packages from source, or simply gaining a clearer picture of your system's package interconnections.


title: CAVEATS
content:
<ul><li>The command relies on the metadata from your currently enabled DNF repositories. If a required repository is not enabled, dependencies from that repository may not be resolved or listed.</li><li>The output can be extensive, especially for packages with many dependencies or when using the `--all` or `--verbose` options. Piping the output to tools like `less` or `grep` is often advisable for better readability.</li><li>`dnf-deplist` shows resolved dependencies based on the current system state and available packages, which might differ from a theoretical list of dependencies found directly in an RPM file's header if not all dependencies are met by available packages.</li></ul>


title: OUTPUT FORMAT
content:
The output typically lists the package name, followed by the dependency requirement, the type of dependency (e.g., `requires`), and the package that provides that dependency (if found). For example, a line might look like: <br>`package-name requires /usr/bin/python3 provided by python3-libs-X.Y.Z.rpm` <br>When using `--verbose`, more detailed information about the NEVRA (Name-Epoch-Version-Release-Architecture) of the providing package is included.


title: COMMON USE CASES
content:
<ul><li><b>Troubleshooting Missing Dependencies</b>: Quickly identify which packages are missing or not satisfied during an installation or upgrade failure.</li><li><b>Building from Source</b>: Understand the build-time requirements for compiling software on your system.</li><li><b>System Auditing</b>: Gain insight into the interdependencies of installed software, which can be crucial for security audits or system hardening.</li><li><b>Package Development</b>: Verify that package specifications correctly declare all necessary dependencies.</li></ul>


title: HISTORY
content:
The `deplist` functionality originated in the YUM package manager, serving as a critical tool for dependency introspection. With the transition from YUM to DNF (Dandified YUM) as the default package manager in Fedora and later in RHEL/CentOS, this utility was re-implemented and integrated into DNF. While DNF introduced a new underlying resolver (`libsolv`), the purpose and core functionality of `deplist` remained consistent: to provide a clear, detailed view of package dependencies for effective system management and troubleshooting. Its continued presence highlights its importance in the Linux package management ecosystem.


title: PARAMETERS
content:
<b><b>-novid</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Skips the Valve intro video when the game launches.<br><br><b><b>-nojoy</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Disables joystick support, which can resolve some input conflicts.<br><br><b><b>-high</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Starts the game process with high CPU priority.<br><br><b><b>-low</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Starts the game process with low CPU priority.<br><br><b><b>-fullscreen</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Launches the game in fullscreen display mode.<br><br><b><b>-windowed</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Launches the game in windowed display mode.<br><br><b><b>-noborder</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;When used with <b>-windowed</b>, removes the window border.<br><br><b><b>-w &lt;width&gt;</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets the game's initial resolution width (e.g., <b>-w 1920</b>).<br><br><b><b>-h &lt;height&gt;</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets the game's initial resolution height (e.g., <b>-h 1080</b>).<br><br><b><b>-freq &lt;rate&gt;</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets the monitor's refresh rate (e.g., <b>-freq 144</b>). Also seen as <b>-refresh</b>.<br><br><b><b>-console</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Opens the in-game developer console upon launching the game.<br><br><b><b>-exec &lt;filename&gt;</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Executes a specified configuration file (e.g., <b>-exec autoexec.cfg</b>) after default configs.<br><br><b><b>-language &lt;lang&gt;</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets the game's display language (e.g., <b>-language english</b>).<br><br><b><b>-threads &lt;count&gt;</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the number of CPU threads the game should use. Often auto-detected, but can be set manually (e.g., <b>-threads 8</b>).<br><br><b><b>-vulkan</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Forces the game to use the Vulkan rendering API on supported systems, often beneficial for Linux performance via Proton.<br><br><b><b>+&lt;cvar&gt; &lt;value&gt;</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Executes a console variable (Cvar) command with a specified value upon startup (e.g., <b>+cl_showfps 1</b>).<br><br>


title: DESCRIPTION
content:
Counter-Strike 2 (CS2) is a highly competitive, team-based tactical first-person shooter developed by Valve. It serves as a free upgrade to Counter-Strike: Global Offensive (CS:GO), bringing the beloved franchise to the Source 2 engine. Players engage in objective-based rounds, primarily as terrorists attempting to plant a bomb or hostages, or as counter-terrorists trying to prevent the bomb or rescue hostages. Its core gameplay revolves around precise gunplay, strategic utility usage (grenades), and intricate map control. CS2 features updated maps, volumetric smokes, improved visual fidelity, and a sub-tick update system for more responsive gameplay. On Linux, CS2 is typically run through Steam Play, utilizing Valve's Proton compatibility layer, which allows Windows-native games to run on Linux distributions.


title: CAVEATS
content:
Counter-Strike 2 is not a traditional Linux command-line utility. It's a commercial video game primarily distributed and launched via the Steam client. The "command-line options" listed are typically entered into the game's "Launch Options" within the Steam client for CS2. Direct execution of a 'cs2' binary from a standard Linux shell is usually not how the game is intended to be launched, as it relies on Steam's environment and Proton for compatibility on Linux.


title: LAUNCH VIA STEAM
content:
On Linux, CS2 is almost exclusively launched through the Steam client. To use the command-line options listed, navigate to your Steam Library, right-click on Counter-Strike 2, select 'Properties', and then enter the desired options in the 'Launch Options' text box under the 'General' tab. Steam then passes these arguments to the game's executable.


title: PROTON COMPATIBILITY LAYER
content:
Since Counter-Strike 2 is developed for Windows, its execution on Linux relies on Proton, a compatibility layer developed by Valve. Proton integrates Wine and other components to translate Windows API calls into Linux equivalents, allowing the game to run. Users may need to ensure Proton is enabled for CS2 in Steam's compatibility settings.


title: CONFIGURATION FILES
content:
Many in-game settings and custom commands can be persistently stored in configuration files. The primary user configuration file is <i>config.cfg</i>, located in the game's user data directory (e.g., <i>~/.steam/steam/steamapps/common/Counter-Strike Global Offensive/cs2/cfg/</i>). Users often create an <i>autoexec.cfg</i> in the same directory to automatically execute custom commands and bind keys upon game startup.


title: HISTORY
content:
Counter-Strike 2 is the latest iteration in the Counter-Strike series, which began in 1999 as a Half-Life mod. It evolved through versions like Counter-Strike 1.6 and Counter-Strike: Source, before the highly successful Counter-Strike: Global Offensive (CS:GO) was released in 2012. CS2 was officially announced and released in September 2023 as a free upgrade to CS:GO, migrating the game to Valve's Source 2 engine. This move brought significant graphical and technical improvements, including physically-based rendering, dynamic smoke effects, and a new 'sub-tick' architecture aimed at improving gameplay responsiveness.


title: TLDR
content:
<b>Run a game with one map</b>`[path/to/cs2] -dedicated +map [de_dust2]`<br><b>Run a game with specified maximum number of players</b>`[path/to/cs2] -dedicated +map [de_dust2] -maxplayers [64]`<br><b>Run a game with specified server IP and port</b>`[path/to/cs2] -dedicated +map [de_dust2] -ip [1.2.3.4] -port [27015]`<br><b>Shut the server down</b>`quit`


title: PARAMETERS
content:
<b>-clear</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Clears the 'away' status by removing the <B>.away</B> file from the user's home directory, indicating the user is no longer away.<br><br><b>message</b><br>&nbsp;&nbsp;&nbsp;&nbsp;(Optional) A text string that will be used as the 'away' message. This message is typically written into the <B>.away</B> file and displayed by `finger`.<br><br>


title: DESCRIPTION
content:
The `away` command, <I>historically found on some Unix-like systems</I>, was used to indicate a user's presence status, primarily for the `finger` utility. When a user was marked 'away,' `finger` would report this status, optionally displaying a custom message provided by the user. This was typically achieved by creating or manipulating a hidden file named <B>.away</B> in the user's home directory.<br><br>The existence of this file would signal the 'away' status, and its content (if any) would be displayed as the away message. Clearing the away status involved removing this <B>.away</B> file. While <I>not commonly available as a standalone command on modern Linux distributions</I>, the concept of an <B>.away</B> file persists in some `finger` implementations.


title: CAVEATS
content:
This `away` command is <I>not a standard or widely available utility</I> on most modern Linux distributions. Its functionality is largely superseded or managed indirectly (e.g., by manually creating/removing a <B>~/.away</B> file, or through more advanced user presence systems). It was more common on older Unix and BSD systems and is primarily relevant in contexts where the `finger` daemon is still actively used for user status.


title: FILE INTERACTION
content:
The `away` command typically creates or removes a hidden file named <B>.away</B> in the user's home directory. The mere presence of this file signifies an 'away' status. If the file contains text, that text is used as the 'away' message by utilities like `finger`.


title: MODERN USAGE CONTEXT
content:
In most modern Linux environments, the `away` command as a standalone utility is absent. If an 'away' status is desired for `finger`, users typically create or remove the <B>~/.away</B> file manually using commands like <B>touch ~/.away</B> or <B>rm ~/.away</B>, potentially piping a message into it (e.g., <B>echo 'On vacation' > ~/.away</B>).


title: HISTORY
content:
The `away` command concept emerged in earlier Unix environments, closely tied to the `finger` protocol and daemon. Its primary role was to allow users to self-report their availability, particularly useful in multi-user mainframe or workstation environments where direct communication might not always be immediate. It pre-dates modern instant messaging or presence services. The specific `away` utility has largely faded from common Linux installations, with its core functionality either becoming less relevant or being absorbed into more complex presence systems or handled by direct file manipulation.


title: TLDR
content:
<b>Lock terminal and set away message</b>`away [message]`<br><b>Lock terminal and enable mail check</b>`away [[-c|--mail]] [message]`<br><b>Lock terminal and disable mail check</b>`away [[-C|--nomail]] [message]`<br><b>Lock terminal and sleep background tasks for number of seconds</b>`away [[-t|--time]] [seconds] [message]`<br><b>Lock terminal and check mail if at least one inbox hasn't received new mail</b>`away [[-p|--persist]] [message]`<br><b>Lock terminal and check mail until at least one inbox has received new mail</b>`away [[-P|--nopersist]] [message]`<br><b>Display help</b>`away [[-h|--help]]`<br><b>Display version</b>`away [[-v|--version]]`


title: PARAMETERS
content:
<b>&lt;<i>package-file</i>|<i>package-spec</i>&gt;</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the target package. This can be the path to an SRPM file (e.g., <i>mypackage-1.0-1.src.rpm</i>), the path to a spec file (e.g., <i>mypackage.spec</i>), or the name of a source package available in enabled repositories (e.g., <i>mypackage</i>).<br><br><b><b>-s</b>, <b>--specfile</b> &lt;<i>specfile</i>&gt;</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Explicitly specifies the path to an RPM spec file from which to read build dependencies. This is useful when the spec file is not part of an SRPM or is located elsewhere.<br><br><b><b>--installroot</b>=&lt;<i>path</i>&gt;</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies an alternative root directory into which dependencies will be installed. This is useful for chroot environments or when preparing a custom build environment without affecting the host system.<br><br><b><b>--buildroot</b>=&lt;<i>path</i>&gt;</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies an alternative build root for installing build dependencies. This is often used in conjunction with <b>--installroot</b> for more granular control over the build environment setup.<br><br><b><b>--enable-source</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Enables the resolution of build dependencies that are themselves source packages (SRPMs) from enabled DNF repositories. This is crucial when a package's build dependencies are not just development libraries but other SRPMs.<br><br><b>[<i>options</i>]</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Represents general DNF options that can be used with <i>dnf-builddep</i>, such as <b>--assumeyes</b> (<b>-y</b>) for automatic confirmation, <b>--nogpgcheck</b> to disable GPG signature checking, or <b>--enablerepo</b>/<b>--disablerepo</b> to manage repositories during dependency resolution.<br><br>


title: DESCRIPTION
content:
The <i>dnf-builddep</i> command is a powerful DNF plugin designed to simplify the process of installing all necessary build dependencies for a specified RPM package. It parses the <i>BuildRequires</i> and <i>Requires(pre)</i> fields from an SRPM (Source RPM) file, a local spec file, or a package name available in configured DNF repositories. After identifying these dependencies, it leverages DNF's robust dependency resolution engine to automatically download and install them. <br><br>This utility is indispensable for package developers, maintainers, and users who need to compile software from source on RPM-based Linux distributions like Fedora, RHEL, CentOS, Rocky Linux, or AlmaLinux. Instead of manually figuring out and installing each required development package, <i>dnf-builddep</i> automates this often complex and error-prone task, ensuring that the build environment is correctly set up before compilation. It significantly streamlines the workflow for rebuilding existing packages or developing new ones.


title: CAVEATS
content:
Requires the <i>dnf-plugins-core</i> package to be installed. <br>The command needs access to configured DNF repositories that contain the necessary build dependencies. <br>It typically requires root privileges to install packages on the system. <br>Be aware that installing build dependencies can pull in a large number of packages, potentially consuming significant disk space.


title: USAGE EXAMPLES
content:
To install build dependencies for an SRPM file:<br><b>sudo dnf builddep mypackage-1.0-1.src.rpm</b><br><br>To install build dependencies for a local spec file:<br><b>sudo dnf builddep -s mypackage.spec</b><br><br>To install build dependencies for a source package named 'mypackage' available in repositories:<br><b>sudo dnf builddep mypackage</b>


title: REQUIRED PACKAGE
content:
The <i>dnf-builddep</i> command is part of the <i>dnf-plugins-core</i> package. Ensure this package is installed on your system to use the command.


title: HISTORY
content:
The <i>dnf-builddep</i> command is the modern successor to the <i>yum-builddep</i> command, which served a similar purpose in the older YUM package manager. With the transition to DNF as the default package manager for Fedora and later for RHEL/CentOS, this essential functionality was migrated and enhanced as a DNF plugin. Its development is intertwined with the evolution of DNF itself, aiming to provide a more robust and performant dependency resolution engine for RPM-based systems, thereby streamlining the software development and packaging workflow within these ecosystems.


title: TLDR
content:
<b>Install dependencies for a given package</b>`dnf builddep [path/to/specification.spec]`<br><b>Install dependencies for a given package but ignore unavailable</b>`dnf builddep --skip-unavailable [path/to/specification.spec]`<br><b>Define the RPM macro to a given expression</b>`dnf builddep [[-D|--define]] '[expression]'`<br><b>Define an argument for a .spec file path</b>`dnf builddep --spec [argument]`<br><b>Define an argument for a .rpm file path</b>`dnf builddep --srpm [argument]`<br><b>Display help</b>`dnf builddep --help-cmd`


title: PARAMETERS
content:
<b><b>-b</b> <i>&lt;bytes&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets the buffer size for entropy collection. Default is typically 128KB.<br><br><b><b>-c</b> <i>&lt;cycles&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the number of cycles to collect per bit. Default 0 enables auto-tuning.<br><br><b><b>-d</b> <i>&lt;N&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Controls daemonization: <i>0</i> for foreground, <i>1</i> for background. Overridden by <b>-F</b>.<br><br><b><b>-F</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Forces <i>haveged</i> to run in the foreground, useful for debugging.<br><br><b><b>-g</b> <i>&lt;group&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the group name or GID under which <i>haveged</i> should run.<br><br><b><b>-i</b> <i>&lt;bytes&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets the amount of entropy (in bytes) to initially fill <i>/dev/random</i> upon startup. Default is typically 1024 bytes.<br><br><b><b>-n</b> <i>&lt;bytes&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Writes the specified number of bytes to the entropy pool and then exits.<br><br><b><b>-p</b> <i>&lt;file&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the path for the PID file.<br><br><b><b>-r</b> <i>&lt;device&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets the path to the entropy output device. Default is <i>/dev/random</i>.<br><br><b><b>-s</b> <i>&lt;file&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies a file to read/write a seed for startup/shutdown.<br><br><b><b>-u</b> <i>&lt;user&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the user name or UID under which <i>haveged</i> should run.<br><br><b><b>-v</b> <i>&lt;N&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets the verbosity level: <i>0</i>=quiet, <i>1</i>=errors, <i>2</i>=info, <i>3</i>=debug.<br><br><b><b>-w</b> <i>&lt;N&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets the entropy watermark in bits. <i>haveged</i> tries to keep entropy above this level. Default is typically 1024 bits.<br><br><b><b>--version</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays version information and exits.<br><br><b><b>--help</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays a help message and exits.<br><br>


title: DESCRIPTION
content:
<i>haveged</i> is a user-space daemon that continuously feeds the Linux kernel's entropy pool, crucial for <i>/dev/random</i> and <i>/dev/urandom</i>. It is particularly valuable in environments where traditional hardware entropy sources are scarce, such as virtual machines, embedded systems, or new server installations. <i>haveged</i> generates high-quality random numbers by measuring microscopic, unpredictable variations in CPU instruction execution times (CPU jitter). This software-based method ensures a steady supply of entropy, preventing applications from blocking when requesting cryptographically secure random data from <i>/dev/random</i> and generally enhancing system security by providing sufficient randomness for cryptographic operations.


title: CAVEATS
content:
While <i>haveged</i> provides a robust software-based entropy source, systems with dedicated hardware Random Number Generators (RNGs) might not strictly require it, or can use it as a supplement.<br>The quality of entropy from CPU jitter is widely accepted but relies on the unpredictability of timing, which differs from true physical noise sources.<br>Ensure proper user/group permissions if running <i>haveged</i> with custom settings to avoid security issues.


title: SYSTEMD INTEGRATION
content:
On modern Linux distributions, <i>haveged</i> is typically managed as a <i>systemd</i> service. This ensures that it starts automatically at boot time, making entropy available early for critical system operations such as SSH key generation or SSL certificate creation.


title: ENTROPY FOR CRYPTOGRAPHY
content:
Sufficient entropy is vital for strong cryptographic keys and operations. <i>haveged</i> helps ensure that applications requiring cryptographically secure random numbers (e.g., <i>OpenSSL</i>, SSH daemons) always have a non-blocking source of high-quality randomness.


title: HISTORY
content:
<i>haveged</i> was developed by Stephen Early to address the common problem of entropy starvation, particularly in virtualized environments, containers, or embedded systems where traditional entropy sources (like disk I/O or user input) are scarce. Its development focused on providing a self-contained, software-only solution for generating high-quality random data by exploiting CPU timing jitter. It has become a crucial component in many Linux distributions to ensure sufficient entropy for cryptographic operations, preventing performance bottlenecks and enhancing system security.


title: TLDR
content:
<b>Generate a random number</b>`sudo haveged`<br><b>Run haveged in foreground</b>`sudo haveged [[-F|--Foreground]]`<br><b>Set file path for output of haveged</b>`sudo haveged [[-f|--file]] [path/to/file]`<br><b>Set run level for daemon</b>`sudo haveged [[-r|--run]] [runlevel]`<br><b>Set collection buffer size in kibibyte words</b>`sudo haveged [[-b|--buffer]] [buffersizeinKW]`<br><b>Insert a command to an already running haveged process or daemon</b>`sudo haveged [[-c|--command]] [command]`<br><b>Set cache size in kibibyte words</b>`sudo haveged [[-d|--data]] [cachesizeinKW]`<br><b>Set number of bytes to write to the output file</b>`sudo haveged [[-n|--number]] [byteamount]`


title: PARAMETERS
content:
<b>--cpu <N></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the number of CPU stressors to run, consuming CPU cycles.<br><br><b>--vm <N></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Runs N virtual memory stressors, allocating and deallocating memory.<br><br><b>--io <N></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Starts N I/O stressors, performing various synchronous and asynchronous I/O operations.<br><br><b>--disk <N></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Activates N disk I/O stressors, writing and reading files to consume disk bandwidth.<br><br><b>--timeout <N>s|m|h</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets a time limit for the stress test (e.g., 60s, 5m, 1h).<br><br><b>--metrics</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays metrics on the stressor performance at the end of the run.<br><br><b>--verbose</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Enables verbose output, showing more details about the stress test progress.<br><br><b>--all <N></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Runs all available stressors, each with N workers. Use with caution as it consumes significant resources.<br><br><b>--vm-bytes <SIZE></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the amount of memory to allocate for each virtual memory stressor (e.g., 256M, 1G).<br><br><b>--hdd-bytes <SIZE></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets the amount of data to write/read for each disk stressor (e.g., 10G).<br><br>


title: DESCRIPTION
content:
<b>stress-ng</b> is a comprehensive workload generator designed to stress test a wide range of Linux system components. It can apply configurable stress to the CPU, memory, disk I/O, networking, and various kernel subsystems. The tool aims to discover hardware flaws, operating system bugs, and performance bottlenecks under extreme load. Users can specify the type and intensity of stress using numerous options, allowing for highly targeted testing of specific system resources or complex, multi-component workloads. It provides a robust way to validate system stability, benchmark performance, and ensure reliability before deployment, making it invaluable for developers, system administrators, and quality assurance engineers. Its flexible design allows it to simulate real-world usage patterns or push systems to their absolute limits, helping identify weak points and improve system resilience.


title: CAVEATS
content:
<b>stress-ng</b> can push system resources to their absolute limits, potentially leading to system instability, unresponsiveness, or even crashes. It's crucial to use it with caution, especially in production environments or on systems containing unsaved work. Always understand the type and intensity of stress being applied to avoid unexpected outages or data loss. High resource consumption is an intended outcome.


title: EXTENSIVE STRESSOR TYPES
content:
Beyond basic CPU and memory, <b>stress-ng</b> offers hundreds of distinct stressors, including specific types of floating-point math, various I/O patterns, file system operations, process creation/destruction, context switching, locking mechanisms, and many more. This allows for highly targeted testing of very specific system behaviors and kernel components, making it a powerful diagnostic tool.


title: HISTORY
content:
<b>stress-ng</b> was developed by Colin King as a modern and highly configurable successor to the simpler <b>stress</b> tool. Its development focused on providing a much wider array of stressors covering various system components, from CPU and memory to I/O, networking, and kernel subsystems. It aims to provide a robust framework for identifying hardware and software flaws under extreme load, continuously evolving to include new workload types and system testing capabilities.


title: TLDR
content:
<b>Stress all CPUs with 4 workers for 60 seconds</b>`stress-ng [[-c|--cpu]] 4 [[-t|--timeout]] 60s`<br><b>Stress virtual memory with 2 workers for 30 seconds</b>`stress-ng [[-m|--vm]] 2 --vm-bytes [512M] [[-t|--timeout]] 30s`<br><b>Stress the I/O subsystem with 3 workers for 45 seconds</b>`stress-ng [[-i|--io]] 3 [[-t|--timeout]] 45s`<br><b>Run all stress tests for 2 minutes</b>`stress-ng [[-a|--all]] [1] [[-t|--timeout]] 2m`


title: PARAMETERS
content:
<b><i>-r, --revision &lt;REVISION&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies one or more revisions whose parents should be simplified. This option can be used multiple times to target several commits. If no revisions are provided, the command operates on the working copy's current commit.<br><br><b><i>-p, --parent &lt;REVISION&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Defines a specific parent revision to consider for removal. This option can be specified multiple times. If provided, only these specified parents are checked for redundancy and potentially removed. If not specified, the command automatically identifies and removes all redundant parents.<br><br>


title: DESCRIPTION
content:
The <b>jj simplify-parents</b> command is a powerful tool within the Jujutsu (jj) version control system designed to clean up and simplify the parent structure of commits. It identifies and removes redundant merge parents from commits, where a parent is considered redundant if it is an ancestor of another parent of the same commit. This often occurs in scenarios like merging a branch back into its ancestor, leading to unnecessarily complex and cluttered commit graphs. <br><br>While this command rewrites the specified commits, it guarantees that the commit's content (the 'tree') remains unchanged. Its primary purpose is to make the commit history cleaner and easier to understand without altering the functional state of the code. It helps in maintaining a tidy and linear-looking history, which can improve readability and simplify operations that traverse the commit graph. By default, if no revisions are specified, it operates on the working copy's commit.


title: CAVEATS
content:
Using <b>jj simplify-parents</b> rewrites the history of the specified commits, meaning their commit IDs will change. While the command preserves the commit's content (tree), any operations or references that rely on the old commit IDs (e.g., external tools, bookmarks, or scripts) will need to be updated. It's generally recommended to use this command with caution, especially on shared history, and to communicate changes to collaborators if the affected commits have been published.


title: JUJUTSU (JJ) CONTEXT
content:
The command <b>jj simplify-parents</b> is a subcommand of the Jujutsu (jj) version control system, not a standalone Linux command named <b>jj-simplify-parents</b>. To execute it, you must have Jujutsu installed and invoke it via the <b>jj</b> executable, followed by the subcommand name.


title: HISTORY
content:
The <b>simplify-parents</b> subcommand is an integral part of the Jujutsu (jj) version control system, which was designed from the ground up to address common complexities and frustrations found in traditional VCS like Git. Introduced early in jj's development, it embodies jj's philosophy of offering powerful, intuitive tools for manipulating and cleaning up commit history. It specifically targets the common issue of redundant merge parents, a problem that often arises in Git when merging branches that have already converged or been rebased, leading to an unnecessarily bushy and confusing commit graph. This command provides a clean solution without altering the committed code.


title: TLDR
content:
<b>Simplify parent edges of given revisions</b>`jj simplify-parents [[-r|--revisions]] [revsets]`<br><b>Simplify parent edges of given revisions and trees of their descendants</b>`jj simplify-parents [[-s|--source]] [revsets]`


title: PARAMETERS
content:
<b><i>subcommand</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;The specific operation to perform on Git remotes. Common subcommands include <b>fetch</b>, <b>push</b>, <b>track</b>, <b>untrack</b>, and <b>list</b>.<br><br><b>fetch</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Fetches new changes and remote branches from a configured Git remote into the Jujutsu repository.<br><br><b>push</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Pushes local Jujutsu changes (commits and branches) to a configured Git remote.<br><br><b>track <I>GIT_REMOTE_BRANCH</I> <I>JJ_BRANCH</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Configures a Jujutsu branch (<I>JJ_BRANCH</I>) to track a specific Git remote branch (<I>GIT_REMOTE_BRANCH</I>), establishing a one-to-one relationship.<br><br><b>untrack <I>GIT_REMOTE_BRANCH</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Removes the tracking configuration for a Git remote branch, disassociating it from any Jujutsu branch.<br><br><b>list</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Lists all configured Git remotes, their URLs, and their tracking relationships with Jujutsu branches.<br><br><b>--remote <I>NAME</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the name of the Git remote to interact with (e.g., 'origin', 'upstream'). This option is common for <b>fetch</b> and <b>push</b>.<br><br><b>--branch <I>NAMES</I>...</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies one or more branches to fetch or push. Can be used multiple times to include multiple branches.<br><br><b>--all</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Used with 'fetch' or 'push' to operate on all branches configured for the remote.<br><br><b>--force</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Forces the push operation, potentially overwriting remote history. Use with extreme caution as this can lead to data loss.<br><br><b>--rebase</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Used with 'fetch' to automatically rebase local branches on top of their newly fetched remote counterparts after fetching.<br><br><b>--json</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Outputs command results in JSON format, which is useful for scripting and programmatic integration.<br><br>


title: DESCRIPTION
content:
<b>jj-git-remote</b> is an external command within the Jujutsu (<b>jj</b>) version control system that facilitates seamless interaction with Git remotes. While <b>jj</b> introduces a unique and powerful approach to version control, it acknowledges the prevalent use of Git. This command acts as a crucial bridge, enabling <b>jj</b> users to fetch updates from and push local changes to existing Git repositories. It handles the necessary underlying Git operations, abstracting away the complexities, to synchronize the <b>jj</b> repository's state with a remote Git server. This interoperability is vital for collaborative workflows, allowing teams to mix <b>jj</b> and traditional Git users, or for integrating <b>jj</b> into existing Git-centric pipelines without disruption. It ensures that Jujutsu repositories can fully participate in the broader Git ecosystem.


title: CAVEATS
content:
Understanding the differences between Jujutsu's internal data model and Git's is crucial for effective use of <b>jj-git-remote</b>. While it bridges the gap, concepts like 'branches' and 'history' are managed differently. Force pushing (with <code>--force</code>) can lead to irreversible loss of remote history and should be used with extreme caution. The command's behavior and available options may evolve as Jujutsu is under active development.


title: INTERACTION MODEL
content:
The <b>jj-git-remote</b> command manages the synchronization between Jujutsu's internal repository state and a Git remote. When fetching, it pulls Git references (branches, tags) into a dedicated 'git/' namespace within the Jujutsu repository's ref store. When pushing, it translates Jujutsu changes (such as new commits and branch movements) into standard Git objects and references, ensuring the underlying Git repository remains compatible with standard Git clients.


title: REMOTE CONFIGURATION
content:
Git remotes for <b>jj</b> are configured within the Jujutsu repository's configuration. This is typically done in the <code>.jj/repo/config.json</code> file or through global <b>jj</b> configuration settings. The configuration specifies the URL of the remote and can include other options like default branches for fetching/pushing, similar to how Git itself manages remotes.


title: HISTORY
content:
Jujutsu (<b>jj</b>) was developed by Martin Pool as a modern, user-friendly alternative to Git, aiming to improve upon Git's command line interface and data model. The <b>jj-git-remote</b> command was an integral part of <b>jj</b> from its early stages, designed to provide essential interoperability with the widely adopted Git ecosystem. This allows <b>jj</b> users to interact with existing Git repositories, fetching and pushing changes without needing to switch back to native Git commands, thus facilitating a smooth transition and mixed-environment workflows. Its existence underscores the practical necessity of integrating with established version control systems for real-world adoption.


title: TLDR
content:
<b>List all Git remotes</b>`jj git remote list`<br><b>Add a Git remote</b>`jj git remote add [remote] [url]`<br><b>Change the URL of a Git remote</b>`jj git remote set-url [remote] [url]`<br><b>Remove a Git remote</b>`jj git remote remove [remote]`<br><b>Rename a Git remote</b>`jj git remote rename [old_name] [new_name]`


title: PARAMETERS
content:
<b><b>-r</b>, <b>--repo</b> <I>PATH</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the path to the repository root directory to initialize. If not provided, it defaults to the current directory.<br><br><b><b>--sparse</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Initializes the repository with a sparse working copy, meaning only files tracked by Jujutsu will be included in the working directory.<br><br>


title: DESCRIPTION
content:
<i>jj-git-init</i> creates a new Jujutsu (jj) repository in the current directory or a specified path, simultaneously initializing a Git repository as its backend. This command allows users to leverage Jujutsu's advanced features, such as rebase by default, explicit state, and powerful conflict resolution, while maintaining compatibility with the Git ecosystem. It is particularly useful for those transitioning from Git, working on projects already managed by Git, or needing to push to and pull from remote Git repositories seamlessly. The command sets up the necessary internal structure for Jujutsu to manage commits, branches, and the working copy, with Git serving as the underlying storage layer. This hybrid setup simplifies workflows that involve both Git and Jujutsu operations.


title: CAVEATS
content:
This command requires Git to be installed and accessible in your system's PATH. While it uses Git as a backend, direct manipulation of the underlying Git repository using standard Git commands is generally discouraged, as Jujutsu manages its state and might not always reflect a state directly interpretable by Git. It is best to interact primarily through <i>jj</i> commands. This command initializes a new Git repository; it does not take over an existing Git repository's <i>.git</i> directory.


title: BACKEND TYPE
content:
Unlike the generic <i>jj init</i> command, <i>jj-git-init</i> explicitly and exclusively initializes a Jujutsu repository with a Git backend. This makes it the preferred command when Git compatibility and interaction with Git remotes are primary requirements.


title: GIT COMPATIBILITY
content:
The repository created by <i>jj-git-init</i> is fully compatible with Git remotes. This enables <i>jj</i> to push changes to and pull changes from standard Git repositories, making it easy to integrate Jujutsu into existing Git-centric development workflows without disruption.


title: HISTORY
content:
Jujutsu (jj) is a modern, experimental version control system designed to be a more user-friendly and powerful alternative to Git. The <i>jj-git-init</i> command is central to its design philosophy of interoperability, allowing users to leverage Jujutsu's innovative features while still collaborating with Git users and infrastructure. It was developed to simplify the transition for Git users and ensure seamless integration with existing Git workflows.


title: TLDR
content:
<b>Create a new Git backed repo in the current directory</b>`jj git init`<br><b>Create a new Git backed repo in the given directory</b>`jj git init [path/to/directory]`<br><b>Initialize the Jujutsu repository as a valid Git repository (allowing the use of both jj and git commands in the same directory)</b>`jj git init --colocate`<br><b>Initialize the Jujutsu repository backed by an existing Git repository</b>`jj git init --git-repo [git_repo]`


title: SYNOPSIS
content:
<b>nagios3</b> [-<b>v</b>] [-<b>d</b>] [-<b>f</b> <i>config_file</i>] [-<b>u</b> <i>user</i>] [-<b>g</b> <i>group</i>] [-<b>p</b> <i>pid_file</i>] [-<b>c</b> <i>command_file</i>] [-<b>s</b>] [-<b>r</b>] [-<b>m</b>] [-<b>V</b>] [-<b>L</b> <i>log_level</i>] [-<b>e</b>] [-<b>N</b>]


title: PARAMETERS
content:
<b>-<b>v</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Verify configuration files and exit. This performs a comprehensive check for errors in the Nagios configuration.<br><br><b>-<b>d</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Start Nagios in daemon mode. This is the typical way Nagios runs in the background.<br><br><b>-<b>f</b> <i>config_file</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specify the main Nagios configuration file to use. This file typically includes or points to other configuration files.<br><br><b>-<b>u</b> <i>user</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Run Nagios as the specified user. This is important for security best practices.<br><br><b>-<b>g</b> <i>group</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Run Nagios as the specified group. Used in conjunction with the <b>-u</b> option.<br><br><b>-<b>p</b> <i>pid_file</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specify an alternate PID file where the process ID of the Nagios daemon will be stored.<br><br><b>-<b>c</b> <i>command_file</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Use specified external command file. This file is used for writing commands to Nagios, such as disabling notifications or scheduling checks.<br><br><b>-<b>s</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Dump program status and statistics to standard output and exit. Useful for quick checks of the daemon's internal state.<br><br><b>-<b>r</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Restart the Nagios daemon. This usually sends a SIGHUP signal to an existing Nagios process, causing it to reload its configuration.<br><br><b>-<b>m</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Do not set up signal handlers. This is typically used for debugging purposes.<br><br><b>-<b>V</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Print version information to standard output and exit.<br><br><b>-<b>L</b> <i>log_level</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Set the daemon's log level (e.g., <i>info</i>, <i>debug</i>, <i>warning</i>). This controls the verbosity of log messages.<br><br><b>-<b>e</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Perform environment checks before starting. This helps ensure necessary prerequisites are met.<br><br><b>-<b>N</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Don't perform any external command checks. Useful when debugging configuration or startup issues.<br><br>


title: DESCRIPTION
content:
<i>nagios3</i> refers to Nagios Core version 3, a powerful, open-source monitoring system designed to keep tabs on IT infrastructure. It provides comprehensive monitoring of hosts, services, network protocols, applications, and more, ensuring the availability and performance of critical systems.<br><br>Nagios proactively identifies problems, such as overloaded servers, crashed applications, or unreachable network devices, before they impact end-users. When issues arise, it can send alerts via various notification methods, including email, SMS, and custom scripts. The system tracks the state of monitored objects, records event logs, and provides a historical record of alerts and recoveries. Its highly extensible plugin architecture allows users to monitor virtually any aspect of their environment, making it a flexible solution for diverse IT landscapes. While <i>nagios3</i> is the core daemon executable, it is typically managed by init scripts or systemd rather than being run directly by users.


title: CAVEATS
content:
<i>nagios3</i> is an older version of Nagios Core, largely superseded by Nagios 4 and the commercial Nagios XI. It is primarily run as a background daemon and typically managed by system init scripts (e.g., <i>systemctl</i>, <i>/etc/init.d/nagios3</i>) rather than being executed directly by end-users. Configuring Nagios can be complex due to its reliance on multiple configuration files and a specific syntax. While powerful, its web interface and some features may appear dated compared to modern monitoring solutions.


title: CONFIGURATION FILES
content:
Nagios relies heavily on a structured set of configuration files to define what to monitor and how. These include the main <i>nagios.cfg</i>, and separate files for hosts (<i>hosts.cfg</i>), services (<i>services.cfg</i>), commands (<i>commands.cfg</i>), contacts (<i>contacts.cfg</i>), timeperiods, and host/service groups. These files are typically located in <i>/etc/nagios3/</i> or <i>/usr/local/nagios/etc/</i>.


title: WEB INTERFACE
content:
A key component of Nagios 3 is its comprehensive web-based user interface, usually accessible via a web server like Apache. This interface provides real-time status dashboards, historical reports, alert summaries, and allows users to acknowledge problems, schedule downtime, and submit passive checks.


title: PLUGINS
content:
Nagios's flexibility comes from its extensive plugin architecture. Nagios plugins are external executables (scripts or compiled programs) that perform checks on hosts and services. Nagios itself simply executes these plugins and processes their output to determine the state of a monitored object (OK, WARNING, CRITICAL, UNKNOWN).


title: HISTORY
content:
Nagios was originally created by Ethan Galstad in 1999 as "NetSaint." Due to trademark issues, it was rebranded as "Nagios" in 2002. Nagios 3 was a significant evolutionary step, released around 2007, bringing improved performance, better scalability, and enhanced features over its predecessors. It established Nagios as one of the leading open-source monitoring solutions. Although it remains functional, development has since moved to Nagios 4 and newer versions, including the commercial Nagios XI. Nagios 3 installations are still found in legacy environments.


title: TLDR
content:
<b>Start nagios3</b>`nagios3 /etc/nagios3/nagios.cfg`<br><b>Start nagios3 in daemon mode</b>`nagios3 -d`<br><b>Start nagios3, print service check scheduling information to stdout, then shutdown</b>`nagios3 -s`<br><b>Verify configuration file</b>`nagios3 -v`


title: PARAMETERS
content:
<b>-h, --host <i><hostname></i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the Redis server hostname or IP address. Default is 127.0.0.1.<br><br><b>-p, --port <i><port></i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets the Redis server port number. Default is 6379.<br><br><b>-a, --password <i><password></i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Provides the password to authenticate with the Redis server.<br><br><b>-n, --db <i><database_number></i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Selects the Redis logical database number. Default is 0.<br><br><b>-f, --file <i><filepath></i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Executes SQL commands from the specified file instead of stdin.<br><br><b>--csv</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Outputs results in CSV format.<br><br><b>--json</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Outputs results in JSON format.<br><br><b>--no-header</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Suppresses the header row in table output.<br><br><b>--help</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays help information and exits.<br><br><b>--version</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Shows the version information and exits.<br><br>


title: DESCRIPTION
content:
The <b>rsql</b> command provides a powerful SQL-like interface for interacting with <B>Redis</B> databases. It allows users familiar with traditional relational database query languages (like SQL) to query and manipulate data stored in Redis, abstracting away the native Redis commands. This tool bridges the gap between the NoSQL nature of Redis and the comfort of SQL for many developers and administrators. It translates SQL queries into appropriate Redis commands, executes them, and formats the results in a readable manner, often as tables. <br><br>While not a standard Linux utility in the same vein as `ls` or `grep`, <b>rsql</b> is a specialized client designed to simplify Redis operations, making it accessible to a wider audience without needing to master Redis's specific command set.


title: CAVEATS
content:
<b>rsql</b> is a third-party client and not part of the standard Redis distribution or a default Linux installation. Its availability depends on whether it has been specifically installed on the system. <br><br>While it provides a SQL-like interface, it does not support the full breadth of SQL features, as Redis is a NoSQL database with a different data model. Complex joins, advanced aggregations, or transactional integrity mechanisms common in relational databases might be limited or unsupported. Users should be aware of the specific SQL subset implemented by their version of <b>rsql</b>.


title: HISTORY
content:
The <b>rsql</b> tool emerged as a community-driven effort to enhance Redis's accessibility, particularly for users accustomed to relational databases. Its development was motivated by the desire to allow data analysts, developers, and administrators to leverage their existing SQL knowledge to interact with Redis, thereby reducing the learning curve associated with Redis-specific commands. It acts as an abstraction layer, translating familiar SQL queries into native Redis operations, reflecting a common trend in the NoSQL ecosystem to provide SQL-compatible interfaces.


title: TLDR
content:
<b>Enter interactive mode</b>`rsql`<br><b>Connect to a database (e.g. PostgreSQL)</b>`rsql --url "[postgresql://user:pass@localhost/mydb]"`<br><b>Connect to a PostgreSQL database with SSL</b>`rsql --url "[postgresql://user:pass@localhost/db?sslmode=require]"`<br><b>Connect to a MySQL database with a specified charset</b>`rsql --url "[mysql://user:pass@localhost/db?charset=utf8mb4]"`<br><b>Run a query and exit</b>`rsql --url "[sqlite://database.db]" -- "[SELECT * FROM users LIMIT 10]"`<br><b>Set default format</b>`rsql --url "[sqlite://db.sqlite]" --format json`<br><b>Connect to file and use custom line separator</b>`rsql --url "[delimited://data.txt?separator=|&has_header=true]"`


title: SYNOPSIS
content:
<b>jj rebase</b> [OPTIONS] { <b>--from</b> &lt;REVISION&gt; <b>--to</b> &lt;REVISION&gt; | <b>--revision</b> &lt;REVISIONS&gt;... <b>--onto</b> &lt;REVISION&gt; | <b>--branch</b> &lt;NAMES&gt;... <b>--onto</b> &lt;REVISION&gt; }


title: PARAMETERS
content:
<b><b>--from</b> &lt;REVISION&gt;</b><br>&nbsp;&nbsp;&nbsp;&nbsp;The old parent(s) of the changesets to be rebased. Specifies the starting point for the rebase range.<br><br><b><b>--to</b> &lt;REVISION&gt;</b><br>&nbsp;&nbsp;&nbsp;&nbsp;The new parent for the changesets that were previously descendants of <b>--from</b>. Specifies the destination parent.<br><br><b><b>--onto</b> &lt;REVISION&gt;</b><br>&nbsp;&nbsp;&nbsp;&nbsp;The new parent for the changesets specified by <b>--revision</b> or <b>--branch</b>. An alternative way to specify the destination.<br><br><b><b>-r</b>, <b>--revision</b> &lt;REVISIONS&gt;...</b><br>&nbsp;&nbsp;&nbsp;&nbsp;The specific changeset(s) to rebase. Multiple revisions can be specified, which will be rebased onto the <b>--onto</b> target.<br><br><b><b>-b</b>, <b>--branch</b> &lt;NAMES&gt;...</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Rebase all changesets on the specified branch(es) onto the <b>--onto</b> target.<br><br><b><b>-s</b>, <b>--source</b> &lt;REVISION&gt;</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Alias for <b>--from</b>, specifying the source parent.<br><br><b><b>-d</b>, <b>--destination</b> &lt;REVISION&gt;</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Alias for <b>--to</b>, specifying the destination parent.<br><br><b><b>-i</b>, <b>--interactive</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Start an interactive rebase session, allowing you to reorder, edit, squash, or split changesets.<br><br><b><b>--insert-after</b> &lt;REVISION&gt;</b><br>&nbsp;&nbsp;&nbsp;&nbsp;When used with interactive rebase, inserts new changesets after the specified revision in the rebase plan.<br><br><b><b>-m</b>, <b>--message</b> &lt;MESSAGE&gt;</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Set the commit message for the new, rebased changeset.<br><br>


title: DESCRIPTION
content:
<i>jj rebase</i> is a fundamental command in the Jujutsu (jj) version control system, used to move or rewrite changesets (commits) by changing their parent. Unlike Git's rebase, which often destructively rewrites history, <i>jj rebase</i> operates on Jujutsu's immutable history model. This means that when a rebase occurs, new changesets are created for the rebased content, while the original changesets are preserved and become hidden. This allows for safer experimentation and easier undo operations. The command is essential for cleaning up commit history, integrating changes from a main branch into a feature branch, or reordering/squashing changesets before merging. It re-applies the differences of the specified changesets relative to their new parent, offering powerful capabilities for history manipulation in a controlled and recoverable manner.


title: CAVEATS
content:
Unlike Git's rebase, <i>jj rebase</i> creates new changesets for the rebased content, preserving the original (now hidden) changesets. This makes rebase operations in Jujutsu inherently non-destructive and easily revertible using commands like <i>jj undo</i> or <i>jj restore</i>. Conflict resolution during rebase requires using <i>jj diff --tool</i> and manually resolving changes, followed by <i>jj new</i> or <i>jj finish</i>.


title: INTERACTIVE REBASE WORKFLOW
content:
The <b>--interactive</b> (<b>-i</b>) flag initiates an interactive rebase. This opens an editor (configured by <b>jj config ui.editor</b>) with a list of changesets to be rebased. Users can then reorder, pick, fold (squash), or edit individual changesets. This powerful feature allows for meticulous refinement of commit history before sharing, making complex history rewrites straightforward.


title: COMMON USAGE PATTERNS
content:
A common use case is to update a feature branch with the latest changes from a main branch: <b>jj rebase -b my-feature -d main</b>. Another is to clean up a series of commits by interactively reordering or squashing them. For example, to interactively rebase the current commit and its ancestors: <b>jj rebase -i -r @-</b> (where <b>@-</b> refers to the parent of the working copy's commit).


title: HISTORY
content:
Jujutsu (jj) is a relatively new version control system, developed by Google, aiming to provide a more intuitive and powerful alternative to Git, especially for large monorepos and complex workflows. Its design is influenced by concepts from Mercurial and Pijul, emphasizing atomic changesets and an immutable history model. <i>jj-rebase</i> is a core command that embodies these principles, offering a flexible and safe way to manipulate commit history, distinguishing itself significantly from Git's rebase due to its non-destructive nature and efficient handling of changesets.


title: TLDR
content:
<b>Move given revisions to a different parent(s)</b>`jj rebase [[-r|--revisions]] [revset] [[-d|--destination]] [revset]`<br><b>Move given revisions and all their descendants</b>`jj rebase [[-s|--source]] [revset] [[-d|--destination]] [revset]`<br><b>Move all revisions in the branch containing given revisions</b>`jj rebase [[-b|--branch]] [revset] [[-d|--destination]] [revset]`<br><b>Move revisions to before and/or after other revisions</b>`jj rebase [[-r|--revisions]] [revset] [[-B|--insert-before]] [revset] [[-A|--insert-after]] [revset]`


title: SYNOPSIS
content:
qemu-system-x86_64 [<i>options</i>] [<i>disk_image</i>] <br><br><b>Example usage:</b><br>&nbsp;&nbsp;qemu-system-x86_64 \<br>&nbsp;&nbsp;&nbsp;&nbsp;-m 2048 \<br>&nbsp;&nbsp;&nbsp;&nbsp;-cpu host \<br>&nbsp;&nbsp;&nbsp;&nbsp;-smp 4 \<br>&nbsp;&nbsp;&nbsp;&nbsp;-drive file=./my_vm.qcow2,format=qcow2 \<br>&nbsp;&nbsp;&nbsp;&nbsp;-cdrom ./ubuntu.iso \<br>&nbsp;&nbsp;&nbsp;&nbsp;-boot d \<br>&nbsp;&nbsp;&nbsp;&nbsp;-enable-kvm \<br>&nbsp;&nbsp;&nbsp;&nbsp;-netdev user,id=vmnic \<br>&nbsp;&nbsp;&nbsp;&nbsp;-device e1000,netdev=vmnic \<br>&nbsp;&nbsp;&nbsp;&nbsp;-vnc :0


title: PARAMETERS
content:
<b>-m <i><megs></i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Set the amount of RAM for the virtual machine in megabytes.<br><br><b>-cpu <i><model></i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specify the CPU model to emulate (e.g., 'host' for host CPU, 'qemu64', 'Haswell').<br><br><b>-smp <i><cpus>[,cores=<cores>][,threads=<threads>][,maxcpus=<maxcpus>]</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Configure the number of virtual CPUs, cores, and threads. 'cpus' is the total number of vCPUs.<br><br><b>-drive <i>file=<path>[,format=<fmt>][,if=<type>][,bus=<bus>]</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Define a storage device. Specify the disk image file, format (e.g., qcow2, raw), interface (e.g., ide, scsi, virtio), and bus.<br><br><b>-hda <i><file></i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Shorthand for <b>-drive file=<file>,if=ide,index=0</b> (main IDE hard disk).<br><br><b>-cdrom <i><file></i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specify a CD-ROM or DVD-ROM image file (e.g., an ISO).<br><br><b>-boot <i><device></i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Set the boot device order ('a' for floppy, 'c' for hard disk, 'd' for CD-ROM, 'n' for network).<br><br><b>-enable-kvm</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Enable KVM hardware virtualization for significantly improved performance (Linux hosts only).<br><br><b>-netdev <i><type>,id=<id>[,options]</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Define a virtual network backend (e.g., 'user' for NAT, 'bridge' for bridged networking, 'tap' for TAP device). Requires a corresponding <b>-device</b>.<br><br><b>-device <i><model>[,netdev=<id>][,options]</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Add a specific virtual device to the VM (e.g., 'e1000' network card, 'virtio-blk' block device, 'VGA' graphics card). For network devices, link to a <b>-netdev</b> ID.<br><br><b>-vnc <i><display></i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Start a VNC server to access the VM's display. '<display>' is usually ':<N>' for display N (e.g., ':0').<br><br><b>-nographic</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Run the VM without a graphical display, useful for headless servers or console-only guests.<br><br><b>-monitor <i><type></i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Connect to the QEMU monitor console (e.g., 'stdio' for standard I/O, 'tcp::<port>' for network).<br><br><b>-daemonize</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Run QEMU in the background, detaching from the terminal.<br><br><b>-usb</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Enable USB support within the virtual machine.<br><br><b>-usbdevice <i><type></i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Add a USB device to the VM (e.g., 'host-vendorid:productid' to pass through a host USB device).<br><br>


title: DESCRIPTION
content:
<i>qemu-system-x86_64</i> is the command-line utility for launching and managing virtual machines that emulate a 64-bit x86 architecture. It is part of the QEMU (Quick EMUlator) suite, a versatile and open-source machine emulator and virtualizer. This specific executable emulates a complete PC system including CPU, memory, and various peripheral devices, allowing unmodified guest operating systems to run.<br><br>While it can purely emulate hardware (which is slower), its primary power comes from its ability to leverage hardware virtualization extensions (like Intel VT-x or AMD-V) via the Linux Kernel-based Virtual Machine (KVM) module. When used with KVM (via the <b>-enable-kvm</b> option), QEMU acts as a hypervisor, providing near-native performance for guest operating systems, making it a robust solution for server virtualization, development environments, and even desktop use.


title: CAVEATS
content:
Using <i>qemu-system-x86_64</i> directly can be complex due to the vast number of options and their interdependencies. Misconfigurations can lead to performance issues or non-booting VMs.<br><br>Optimal performance typically requires KVM acceleration, which is only available on Linux hosts with compatible hardware. Without KVM, performance can be significantly slower due to full software emulation.<br><br>Networking setup can be intricate, requiring understanding of different modes (user, bridge, tap) and potentially host-side network configuration.


title: KVM ACCELERATION
content:
For high performance, always use the <b>-enable-kvm</b> option. This requires a Linux host system with CPU virtualization extensions (Intel VT-x or AMD-V) enabled in the BIOS/UEFI, and the KVM kernel module loaded. Without KVM, QEMU will perform full software emulation, which is considerably slower.


title: QEMU MONITOR
content:
The QEMU Monitor (accessible via <b>-monitor stdio</b> or via VNC console 'Ctrl+Alt+2') is a powerful interface to interact with a running VM. You can issue commands to change disk images, save/restore state, eject CD-ROMs, query device status, and much more. Common commands include 'info status', 'info network', 'savevm', 'loadvm', 'quit'.


title: NETWORKING MODES
content:
QEMU offers several networking modes: <br><b>&nbsp;&nbsp;User-mode networking (-netdev user):</b> Easiest to set up, but guests are behind a NAT, limited to outbound connections and port forwarding. <br><b>&nbsp;&nbsp;Bridged networking (-netdev bridge):</b> Guest gets an IP on the host's LAN, requires a Linux bridge on the host. <br><b>&nbsp;&nbsp;TAP device networking (-netdev tap):</b> Most flexible, allows advanced setups like routing, but requires manual configuration of TAP devices and permissions.


title: HISTORY
content:
QEMU was originally written by Fabrice Bellard and first released in 2000. It quickly gained popularity for its ability to emulate a wide range of architectures and for its 'TCC' (Tiny C Compiler) based dynamic translation. The integration with the Linux Kernel-based Virtual Machine (KVM) in 2007, developed by Avi Kivity, transformed QEMU from primarily an emulator to a full-fledged hypervisor, capable of near-native performance. This synergy (QEMU providing device emulation and KVM handling CPU/memory virtualization) cemented its position as a leading open-source virtualization solution.


title: TLDR
content:
<b>Boot from an image emulating the x86_64 architecture</b>`qemu-system-x86_64 -hda [image_name.img] -m [4096]`<br><b>Boot a QEMU instance from a live ISO image</b>`qemu-system-x86_64 -hda [image_name.img] -m [4096] -cdrom [os_image.iso] -boot d`<br><b>Boot from a physical device (e.g. from USB to test a bootable medium)</b>`qemu-system-x86_64 -hda [/dev/storage_device] -m [4096]`<br><b>Do not launch a VNC server</b>`qemu-system-x86_64 -hda [image_name.img] -m [4096] -nographic`<br><b>Exit non-graphical QEMU</b>`<Ctrl a><x>`<br><b>List the supported machine types</b>`qemu-system-x86_64 [[-M|-machine]] help`


title: DESCRIPTION
content:
<i>tzconfig</i> is a legacy command, primarily found on Debian-based systems (like Ubuntu), used for interactively configuring the system's timezone. It typically presents a menu-driven interface, guiding the user through the selection of their geographical region and then a specific city within that region. This process updates the <b>/etc/timezone</b> file with the chosen timezone name and manages the <b>/etc/localtime</b> symbolic link (or copies the appropriate zone information file) to point to the correct timezone data from <b>/usr/share/zoneinfo</b>.<br><br>While still present on some systems for backward compatibility, its functionality has largely been superseded by more modern and robust tools like <b>timedatectl</b> on systems utilizing <i>systemd</i>, or by directly manipulating the timezone configuration files. Its main utility lies in its user-friendly, interactive nature, making it accessible for non-expert users to set up timezones without manual file editing.


title: CAVEATS
content:
<b>Legacy Tool:</b> <i>tzconfig</i> is considered a legacy command. On modern Linux distributions, especially those using <i>systemd</i>, <b>timedatectl</b> is the preferred and more comprehensive utility for managing time, date, and timezone settings.<br><b>Debian/Ubuntu Specific:</b> This command is predominantly found on Debian and Ubuntu systems. Other distributions might employ different tools (e.g., <b>timedatectl</b> on Red Hat/CentOS/Fedora, or dedicated GUI tools).<br><b>Interactive Only:</b> It is designed exclusively for interactive use and is generally unsuitable for scripting without complex automation tools like 'expect', which is usually discouraged in favor of non-interactive methods.


title: CONFIGURATION FILES
content:
<i>tzconfig</i> primarily interacts with two key configuration files:<br><ul><li><b>/etc/timezone</b>: This file stores the name of the configured timezone (e.g., "America/New_York").</li><li><b>/etc/localtime</b>: This is typically a symbolic link (or a copy) to the specific timezone data file located under <b>/usr/share/zoneinfo/</b> (e.g., <b>/usr/share/zoneinfo/America/New_York</b>). Applications read this file to determine the local time.</li></ul>


title: HISTORY
content:
<i>tzconfig</i> has been a standard component on Debian-based systems for many years, providing a straightforward method for users to set their system timezone. It emerged as an accessible interactive configuration tool for the <i>tzdata</i> package, which contains global timezone definitions. With the evolution of Linux distributions and the adoption of unified init systems like <i>systemd</i>, more consolidated utilities such as <b>timedatectl</b> were introduced. These newer tools absorbed the functionalities previously handled by commands like <i>tzconfig</i>, offering broader control over system time. Although <i>tzconfig</i> remains available for simplicity and backward compatibility, its role has diminished in favor of the more comprehensive <b>timedatectl</b> for system-wide time management.


title: TLDR
content:
<b>Restart the GNOME Display Manager application when all users have logged out</b>`gdm-safe-restart`


title: TLDR
content:
<b>Boot from an image emulating the i386 architecture</b>`qemu-system-i386 -hda [image_name.img] -m [4096]`<br><b>Boot a QEMU instance from a live ISO image</b>`qemu-system-i386 -hda [image_name.img] -m [4096] -cdrom [os_image.iso] -boot d`<br><b>Boot from a physical device (e.g. from USB to test a bootable medium)</b>`qemu-system-i386 -hda [/dev/storage_device] -m [4096]`<br><b>Do not launch a VNC server</b>`qemu-system-i386 -hda [image_name.img] -m [4096] -nographic`<br><b>Exit non-graphical QEMU</b>`<Ctrl a><x>`<br><b>List the supported machine types</b>`qemu-system-i386 [[-M|-machine]] help`


title: PARAMETERS
content:
<b>log</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays a chronological log of all operations that have modified the repository. This log includes details like the operation ID, timestamp, description, and the user who performed it. It's analogous to a detailed reflog but for Jujutsu's internal state.<br><br><b>--limit <i>&lt;COUNT&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Used with <i>log</i>, limits the number of operations displayed to the specified count.<br><br><b>--from-script</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Used with <i>log</i>, filters the output to show only operations that originated from scripts.<br><br><b>--no-graph</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Used with <i>log</i>, suppresses the visual graph representation in the output.<br><br><b>--reversed</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Used with <i>log</i>, displays operations in reverse chronological order (oldest first).<br><br><b>--json</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Used with <i>log</i>, outputs the operation log in JSON format, useful for scripting and programmatic access.<br><br><b>restore <i>&lt;OPERATION_ID&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Restores the repository to the state it was in after the specified operation. This acts as a powerful undo mechanism, allowing users to revert to any past point in the repository's history captured in the operation log. The <i>&lt;OPERATION_ID&gt;</i> can be a full or partial ID from the <i>log</i> command.<br><br><b>obliterate <i>&lt;OPERATION_ID&gt;...</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Permanently deletes one or more operations from the repository's history. This is a destructive and irreversible command. It should be used with caution, as it removes the ability to restore to the obliterated operations. It can also reclaim disk space by removing associated objects.<br><br><b>--delete-git-refs</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Used with <i>obliterate</i>, also deletes any Git references that were created by the obliterated operations, ensuring a cleaner removal if the repository interacts with Git.<br><br>


title: DESCRIPTION
content:
The <b>jj operation</b> command group is a fundamental part of the Jujutsu (jj) version control system, allowing users to inspect, restore, and manage the history of changes made to the repository's state. Unlike traditional Git's reflog, Jujutsu's operation log is a persistent, detailed record of every command that modified the repository, including commits, rebases, merges, and pushes. This robust mechanism provides powerful undo capabilities, enabling users to "time travel" to any past state of the repository. It's crucial for understanding the history of modifications and for recovering from unintended changes, making it a cornerstone for Jujutsu's user experience and its non-destructive approach to version control until an operation is explicitly obliterated.


title: CAVEATS
content:
The <b>jj operation</b> commands are specific to the <I>Jujutsu</I> (jj) version control system and are not standalone Linux utilities. <br>The <b>obliterate</b> subcommand is permanent and destructive; use it with extreme caution as data cannot be recovered after obliteration. <br>Jujutsu is under active development, and command behaviors or options may evolve.


title: OPERATION LOG PURPOSE
content:
Unlike Git's reflog, which can expire, Jujutsu's operation log is designed to be a permanent, complete audit trail of every command that altered the repository's state. This allows for unparalleled flexibility in reverting changes and exploring past repository configurations without loss of data, until explicitly obliterated.


title: NON-DESTRUCTIVE BY DEFAULT
content:
A core tenet of Jujutsu is that operations like rebasing or amending are non-destructive. This means the old state is preserved in the operation log. The <b>jj operation</b> commands facilitate this by allowing users to return to any previous state, providing a robust 'undo' functionality that typical Git workflows lack without manual reflog management.


title: HISTORY
content:
The concept of an immutable operation log is central to Jujutsu's design philosophy, introduced early in its development (around 2021-2022). It distinguishes Jujutsu from other VCS by providing a comprehensive, persistent history of all repository modifications, making complex rebases and history rewriting operations safer and fully reversible by default. The <b>jj operation</b> subcommands have been a core component since the initial public releases of Jujutsu, evolving slightly with new options and stability improvements.


title: TLDR
content:
<b>Show operation log</b>`jj [[op|operation]] log`<br><b>Undo the last operation</b>`jj [[op|operation]] undo`<br><b>Undo a given operation</b>`jj [[op|operation]] undo [operation]`<br><b>Restore the repository to its state at a given operation</b>`jj [[op|operation]] restore [operation]`<br><b>Show changes to the repository in an operation</b>`jj [[op|operation]] show [operation]`<br><b>Show stat, summary and patch of modifications of an operation</b>`jj [[op|operation]] show [--stat] [[-s|--summary]] [[-p|--patch]] [operation]`


title: SYNOPSIS
content:
<br><b>nagios</b> [-c <i>&lt;config_file&gt;</i>] [-d] [-v] [-s] [-u <i>&lt;user&gt;</i>] [-g <i>&lt;group&gt;</i>] [-p <i>&lt;pid_file&gt;</i>] [-x <i>&lt;debug_level&gt;</i>] [-V]<br>


title: PARAMETERS
content:
<b>-c <i>&lt;config_file&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies an alternative main configuration file to use instead of the default (`nagios.cfg`).<br><br><b>-d</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Runs the Nagios daemon in the background. This is the typical mode of operation for continuous monitoring.<br><br><b>-v</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Verifies the configuration files for syntax errors, logical issues, and duplicate definitions, then exits. Highly recommended before starting or restarting.<br><br><b>-s</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays program status information to standard output (if compiled with status output support), useful for debugging.<br><br><b>-u <i>&lt;user&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Runs the Nagios daemon as the specified unprivileged user after initialization. Improves security.<br><br><b>-g <i>&lt;group&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Runs the Nagios daemon as the specified unprivileged group after initialization. Improves security.<br><br><b>-p <i>&lt;pid_file&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies an alternative PID file path for the daemon. The PID file contains the process ID of the running Nagios instance.<br><br><b>-x <i>&lt;debug_level&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets the debug level for the daemon, allowing more verbose logging for troubleshooting. Higher numbers mean more detail.<br><br><b>-V</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Prints the Nagios Core version information and exits, useful for verifying the installed version.<br><br>


title: DESCRIPTION
content:
The <b>nagios</b> command primarily refers to the Nagios Core daemon, the heart of the Nagios IT infrastructure monitoring system. While "nagios2" specifically implies version 2.x of this system, the core daemon command itself is typically <b>nagios</b>. It runs in the background, continuously checking the health of hosts, services, and network devices based on predefined configuration files. Nagios uses plugins to execute checks, processing their output to determine the status (OK, WARNING, CRITICAL, UNKNOWN) and triggering notifications or event handlers when issues are detected. It's a foundational tool for proactive system administration, helping identify and resolve problems before they impact users. Its modular design allows extensive customization and integration with various IT environments.


title: CAVEATS
content:
Nagios Core, especially older versions like 2.x, requires significant manual configuration through text files, which can be complex and error-prone for large environments. While powerful, its setup and maintenance demand a deep understanding of its configuration syntax and monitoring principles. It lacks a built-in discovery mechanism, requiring all hosts and services to be manually defined. Performance can become a concern with thousands of checks, and alert fatigue is a common issue if notifications are not carefully managed. Newer versions (Nagios 4.x) offer improvements, but the core configuration paradigm remains similar.


title: CONFIGURATION FILES
content:
Nagios relies heavily on plain-text configuration files, typically located in <i>/usr/local/nagios/etc/</i> or <i>/etc/nagios/</i>. These files define hosts, hostgroups, services, servicegroups, contacts, timeperiods, and commands, dictating exactly what to monitor and how.


title: WEB INTERFACE
content:
Nagios Core includes a basic web interface (CGI-based) for viewing current status, history, reports, and managing downtime. It provides a centralized dashboard for monitoring all configured items and is accessible via a web browser.


title: HISTORY
content:
The Nagios project began in 1999 as "NetSaint" by Ethan Galstad. It was renamed "Nagios" (a recursive acronym for "Nagios Ain't Gonna Insist On Sainthood") in 2002 due to trademark issues. Nagios 2.x, released around 2004-2005, significantly improved upon its predecessors with features like distributed monitoring capabilities and enhanced event handling. This version was widely adopted and formed the basis for many monitoring setups for years. Development continued with Nagios 3.x (2007) and currently Nagios 4.x (2013 onwards), each bringing further scalability, performance, and user interface enhancements while maintaining backward compatibility with much of the core configuration model.


title: TLDR
content:
<b>Start nagios2</b>`nagios2 /etc/nagios2/nagios.cfg`<br><b>Start nagios2 in daemon mode</b>`nagios2 -d`<br><b>Start nagios2, print service check scheduling information to stdout, then shutdown</b>`nagios2 -s`<br><b>Verify configuration file</b>`nagios2 -v`


title: PARAMETERS
content:
<b><B>REMOTE</B></b><br>&nbsp;&nbsp;&nbsp;&nbsp;The name of the remote Git repository to push to. If omitted, Jujutsu typically defaults to 'origin'.<br><br><b><B>--branch</B> &lt;BRANCH&gt;</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Push only the specified branch(es). This option can be used multiple times to push several branches.<br><br><b><B>--all</B></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Push all Git-tracked branches from the local Jujutsu repository to the remote.<br><br><b><B>--force</B>, <B>-f</B></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Force push the changes. This can overwrite remote history and should be used with extreme caution.<br><br><b><B>--dry-run</B></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Perform a trial run without actually pushing any changes, showing what would be done.<br><br><b><B>--purge</B></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Remove remote branches that no longer exist locally in the Jujutsu repository. Use with care as it deletes remote branches.<br><br><b><B>--tool-args</B> &lt;ARGS&gt;</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Pass additional arguments directly to the underlying Git push command executed by Jujutsu.<br><br><b><B>--json</B></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Output the command's status and results in JSON format, suitable for machine parsing.<br><br>


title: DESCRIPTION
content:
<i>jj-git-push</i> is a subcommand within the <B>Jujutsu (jj)</B> version control system, designed to synchronize local Jujutsu changes with a remote Git repository. Unlike the standard <B>git push</B> which primarily operates on Git branches, <B>jj git push</B> focuses on pushing Jujutsu's internal concept of Git-tracked branches and their corresponding commits. This command is essential for users who manage their projects with Jujutsu but need to collaborate with Git users or publish their work to Git-based platforms. It ensures that the state of Git branches on the remote reflects the desired state from the Jujutsu repository, effectively bridging Jujutsu's flexible history management with Git's widely adopted ecosystem.


title: CAVEATS
content:
Using <B>--force</B> (<B>-f</B>) can lead to data loss or conflicts if others have based work on the overwritten history on the remote. Always communicate with your team before force pushing.<br><br>The <B>--purge</B> option can delete remote branches that might still be relevant to other collaborators. Exercise caution and ensure you understand its implications.<br><br><B>jj-git-push</B> operates on Jujutsu's internal representation of Git-tracked branches. While designed for interoperability, it might not always behave identically to a direct <B>git push</B> for complex scenarios or non-standard branch configurations.


title: BRANCH TRACKING AND MAPPING
content:
When using <B>jj git push</B>, Jujutsu maps its internal concept of 'tracked branches' (which are essentially local Jujutsu branches designated to correspond to remote Git branches) to the actual branches on the Git remote. It primarily pushes changes related to these explicitly tracked branches, rather than arbitrary commits or anonymous branch heads.


title: INTEGRATION WITH GIT REMOTES
content:
For <B>jj git push</B> to function, the Jujutsu repository must be configured to track a Git remote. This setup allows Jujutsu to understand which local branches correspond to which remote branches, facilitating the push operation. Jujutsu maintains its own internal state of remote-tracking information, which it uses to guide the push.


title: HISTORY
content:
The <B>Jujutsu (jj)</B> version control system is a relatively new and innovative alternative to Git, aiming to provide a more intuitive and powerful interface for managing code history. <B>jj git push</B> was introduced as a core component of Jujutsu's interoperability layer, allowing Jujutsu users to seamlessly interact with existing Git repositories and collaborate with Git users. Its development reflects the goal of making Jujutsu a viable daily driver for developers, without requiring them to abandon their existing Git infrastructure or workflows.


title: TLDR
content:
<b>Push a bookmark to the given remote (defaults to git.push setting)</b>`jj git push [[-b|--bookmark]] [bookmark] --remote [remote]`<br><b>Push a new bookmark</b>`jj git push [[-b|--bookmark]] [bookmark] [[-N|--allow-new]]`<br><b>Push all tracked bookmarks</b>`jj git push --tracked`<br><b>Push all bookmarks (including new bookmarks)</b>`jj git push --all`<br><b>Push all bookmarks pointing to given revisions</b>`jj git push [[-r|--revisions]] [revset]`<br><b>Push changes/commits by creating new bookmarks (Name format is as per templates.git_push_bookmark setting, defaults to "push-" ++ change_id.short())</b>`jj git push [[-c|--change]] [revset]`<br><b>Push a revision with the given name</b>`jj git push --named [name]=[revision]`


title: DESCRIPTION
content:
<I>The command <b>spf</b> is not a recognized standard utility or program in common Linux distributions. There is no widely available manual page (man page) or package that provides a command specifically named <b>spf</b> as a standalone tool in the official repositories of major Linux distributions like Debian, Ubuntu, Fedora, or RHEL.<br><br>It is highly probable that this refers to a custom script, a very specialized utility not part of mainstream distributions, or a misunderstanding related to the concept of Sender Policy Framework (SPF) DNS records.<br><br>While SPF is a crucial email authentication mechanism used to prevent email spoofing, tools to manage or query SPF records are typically named differently. Examples include <b>spfquery</b> (often part of the <b>libspf2-tools</b> package), or generic DNS lookup utilities like <b>dig</b> or <b>nslookup</b>, which can be used to retrieve SPF records from DNS. A direct <b>spf</b> command is not a common or standard component of Linux systems.<br><br>Therefore, a standard analysis of its syntax, parameters, and typical usage is not possible as it does not exist as a predefined system command.</I>


title: CAVEATS
content:
<I>As <b>spf</b> is not a standard command, any script or program encountered with this name would be custom-made. Its behavior, options, and security implications would depend entirely on its specific implementation by a system administrator or developer. Users should exercise extreme caution if they encounter such a command on an unfamiliar system, as its functionality is undefined and could potentially be malicious or unintended.</I>


title: HISTORY
content:
<I>There is no documented history of a standard <b>spf</b> command within Linux or Unix-like operating systems. It does not appear to be a part of any major distribution's core utilities or common package sets. The acronym 'SPF' primarily refers to Sender Policy Framework, an email validation system designed to prevent email spoofing, which is a DNS record type, not a command-line utility itself.</I>


title: TLDR
content:
<b>Launch spf with a specific path</b>`spf [path/to/directory]`<br><b>Launch spf with multiple paths</b>`spf [path/to/directory1 path/to/directory2 ...]`<br><b>Fix hotkey settings by appending missing keys</b>`spf [[--fh|--fix-hotkeys]]`<br><b>Fix the configuration file by appending missing entries</b>`spf [[--fch|--fix-config-file]]`<br><b>Use specific configuration and hotkey files</b>`spf [[-c|--config-file]] [path/to/config.toml] [[--hf|--hotkey-file]] [path/to/hotkey.toml]`<br><b>Write the path of the first selected file to this file and exit</b>`spf [[--cf|--chooser-file]] [tmp/chooser-result]`<br><b>Show internal configuration and data directory paths</b>`spf [[pl|path-list]]`


title: PARAMETERS
content:
<b><I>REVISION</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the commit to display. This can be a commit ID prefix, a branch name, a tag, or any valid revset expression. If omitted, the command defaults to showing the working copy commit (<I>@</I>).<br><br><b><b>-n</b>, <b>--no-graph</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Prevents the display of the commit graph alongside the commit details.<br><br><b><b>-s</b>, <b>--stats</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Shows a summary of changes (lines added/deleted) for the commit, rather than the full diff content.<br><br><b><b>-p</b>, <b>--patch</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays the full diff of the commit. This is the default behavior if no diff-related options are specified.<br><br><b><b>-P</b>, <b>--no-patch</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Suppresses the display of the diff entirely, showing only the commit's metadata (author, message, etc.).<br><br><b><b>--color-words</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Applies word-by-word coloring to the diff output, making it easier to spot granular changes within lines.<br><br><b><b>--tool</b> <I>&lt;TOOL&gt;</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Uses a specified external diff tool (e.g., <I>meld</I>, <I>vscode</I>) to display the commit's changes.<br><br><b><b>--short</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Provides a concise summary of the commit, typically including the commit ID, author, and the first line of the commit message.<br><br><b><b>--template</b> <I>&lt;TEMPLATE&gt;</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Allows specifying a custom template string for formatting the command's output. Jujutsu uses a powerful template language for highly customizable views.<br><br><b><b>--from</b> <I>&lt;REVISION&gt;</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;When displaying the diff, calculates the changes relative to this specified <I>REVISION</I>, instead of the commit's parent.<br><br><b><b>--to</b> <I>&lt;REVISION&gt;</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;When displaying the diff, calculates the changes up to this specified <I>REVISION</I>, instead of the commit itself.<br><br><b><b>--pager</b> <I>&lt;WHEN&gt;</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Controls when output is piped to a pager (e.g., <I>less</I>). Valid values are <I>auto</I> (default), <I>always</I>, or <I>never</I>.<br><br><b><b>--color</b> <I>&lt;WHEN&gt;</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Controls when output uses colors. Valid values are <I>auto</I> (default), <I>always</I>, or <I>never</I>.<br><br>


title: DESCRIPTION
content:
The <b>jj show</b> command is a fundamental part of the Jujutsu (jj) distributed version control system, designed to display detailed information about a specific commit. When invoked without a specified revision, it defaults to showing the working copy commit (represented by <I>@</I>). This command provides a comprehensive view including the commit's diff (changes introduced), author and committer details, timestamps, and the commit message.<br><br>It serves a similar purpose to <I>git show</I> in Git, allowing users to review modifications and associated metadata before operations like merging, rebasing, or pushing. Its flexibility is enhanced by various options that can control the output format, ranging from showing only statistics to suppressing the diff entirely, or even formatting the output using a custom template.


title: CAVEATS
content:
The <b>jj show</b> command is specific to the Jujutsu (jj) version control system and is not a standard Unix utility. Its <I>REVISION</I> argument utilizes Jujutsu's advanced revset language, which provides powerful but potentially complex ways to specify commits. Custom templates require familiarity with Jujutsu's templating syntax.


title: DEFAULT BEHAVIOR
content:
When no <I>REVISION</I> is provided, <b>jj show</b> defaults to displaying information about the working copy commit (the commit that the current changes are based on, typically referred to as <I>@</I>). This makes it convenient to quickly inspect your current uncommitted changes or the state of your working directory.


title: REVISION SPECIFICATION
content:
Jujutsu commands, including <b>jj show</b>, leverage a powerful 'revset' language for specifying commits. This allows for highly flexible and precise selection of revisions, such as '<I>branch_name</I>', '<I>commit_id_prefix</I>', '<I>@</I>' (working copy), '<I>main::</I>' (all commits reachable from main), or combinations like '<I>branch_a - branch_b</I>'.


title: HISTORY
content:
Jujutsu (jj) is a modern, experimental distributed version control system developed by Martin von Zweigbergk, designed to offer a different approach to common VCS workflows, particularly around mutable history and collaboration. The <b>jj show</b> command is a core component from its early development, reflecting the system's emphasis on providing clear and flexible ways to inspect and understand changes within the repository. It aims to improve upon the usability and power found in traditional VCS tools like Git for certain operations.


title: TLDR
content:
<b>Show commit description and changes in a revision</b>`jj show [revset]`<br><b>Show a summary of changes in a revision</b>`jj show [[-s|--summary]] [revset]`<br><b>Show a histogram of changes in a revision</b>`jj show --stat [revset]`


title: PARAMETERS
content:
<b>--authors <REGEX>...</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Show revisions by authors matching the given regular expression.<br><br><b>-b, --branch <NAME>...</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Display revisions belonging to the specified branch names.<br><br><b>--from-tool <TOOL></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Filter revisions to only show changes made by a specific tool.<br><br><b>--limit <COUNT></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Restrict the number of revisions shown to the specified count.<br><br><b>-m, --message <REGEX>...</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Show revisions with messages matching the given regular expression.<br><br><b>--no-graph</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Disable drawing the graphical representation of the evolution.<br><br><b>--paths <PATH>...</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Show revisions that modify any of the specified file paths.<br><br><b>-r, --revisions <REVISION>...</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Display revisions reachable from the specified revision identifiers. Defaults to the working copy parent (@) if none are given.<br><br><b>--stdin</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Read additional revision identifiers from standard input.<br><br><b>-t, --tag <NAME>...</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Show revisions belonging to the specified tag names.<br><br><b>-T, --template <TEMPLATE></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Format the output using a custom template string. Provides extensive control over displayed information.<br><br>


title: DESCRIPTION
content:
<i>jj-evolog</i> is an experimental command within the Jujutsu (jj) version control system. It provides a unique visualization of how revisions have transformed over time, focusing on their <b>evolution</b> rather than a static history. Unlike traditional log commands, <i>jj-evolog</i> traces how revisions change through operations like <i>jj amend</i>, <i>jj rebase</i>, or <i>jj squash</i>. It displays each generation of a revision, connecting them to their predecessors via 'evolution links'. This command is invaluable for understanding the dynamic nature of history in Jujutsu, helping users track and debug the flow of iterative refinements and history rewrites. It offers a deeper insight into the lineage and transformation of changes within a repository.


title: CAVEATS
content:
This command is currently <b>experimental</b> and its behavior or available options may change in future Jujutsu releases. It is exclusively for use within Jujutsu repositories and requires an understanding of Jujutsu's mutable history model.


title: DEFAULT BEHAVIOR
content:
When invoked without specific revision arguments, <i>jj-evolog</i> defaults to showing the evolution of revisions reachable from the working copy parent (denoted by <b>@</b>).


title: TEMPLATE CUSTOMIZATION
content:
The <i>--template</i> option is extremely powerful, allowing users to define precisely what revision attributes (e.g., <i>rev_id</i>, <i>change_id</i>, <i>description</i>, <i>mutation_id</i>) are displayed and how they are formatted, enabling highly customized views of revision evolution.


title: VISUALIZING HISTORY REWRITES
content:
The primary utility of <i>jj-evolog</i> lies in its ability to clearly visualize the effects of history-rewriting operations like <i>jj amend</i>, <i>jj rebase</i>, and <i>jj squash</i>. It illustrates the 'before' and 'after' states of revisions, connected by their unique evolutionary links, making complex refactoring easier to follow.


title: HISTORY
content:
Jujutsu (jj) is a modern version control system designed for flexible history management. The <i>jj-evolog</i> command was introduced to visually represent Jujutsu's core concept of <b>mutable history</b> and revision evolution. It helps users track how changes are iteratively refined and rewritten, a fundamental aspect of Jujutsu's design philosophy, distinguishing it from traditional, immutable-history VCS tools like Git.


title: TLDR
content:
<b>Show how a revision has evolved over time</b>`jj evolog [[-r|--revisions]] [revsets]`<br><b>Show diff statistics in the evolution log</b>`jj evolog [[-r|--revisions]] [revsets] --stat`<br><b>Show summary of each change in the evolution log</b>`jj evolog [[-r|--revisions]] [revsets] [[-s|--summary]]`


title: SYNOPSIS
content:
There is <i>no standard</i> `minecraft` Linux command with a defined synopsis. The Minecraft game or server is typically launched via a graphical launcher or by invoking the Java Virtual Machine directly on a Minecraft JAR file.


title: DESCRIPTION
content:
The term "minecraft" refers to the popular sandbox video game created by Mojang Studios. It is not a native or pre-installed Linux command-line utility. While the Minecraft game client and server software can be run on Linux operating systems, there isn't a universally recognized or pre-packaged `minecraft` command with a standard set of options or a man page like typical Linux commands such as `ls` or `grep`.<br><br>Users typically interact with Minecraft on Linux by running a dedicated launcher (either the official one or a community-developed alternative like MultiMC) or by directly executing the game's or server's Java Archive (JAR) files using the `java` command. The game's cross-platform nature, built on Java, allows it to run on various operating systems, including Linux, provided a compatible Java Runtime Environment (JRE) is installed.


title: CAVEATS
content:
The 'minecraft' command does <i>not exist natively</i> on Linux distributions. Users must install the game's official launcher, a third-party launcher, or the server software separately. Running Minecraft (client or server) generally requires a compatible Java Runtime Environment (JRE) to be installed on the system.


title: RUNNING MINECRAFT ON LINUX
content:
The Minecraft client is commonly run via the official Minecraft Launcher, which is available for Linux. Alternatively, third-party launchers (e.g., <b>MultiMC</b>, <b>ATLauncher</b>) offer more features and customization. Direct execution of the client JAR file with `java -jar Minecraft.jar` is also possible but less common for end-users.<br><br>Minecraft servers are frequently run directly using the Java command, for example: <br><i>`java -Xmx4G -Xms4G -jar server.jar nogui`</i><br>where `-Xmx` and `-Xms` define memory limits.


title: INSTALLATION METHODS
content:
The official Minecraft Launcher can be downloaded from Mojang's website, often provided as a `.deb` (for Debian/Ubuntu-based systems), `.rpm` (for Fedora/Red Hat-based systems), or a generic `.jar` or executable file. Community-driven packaging methods like <b>Snap</b> or <b>Flatpak</b> also provide convenient and sandboxed ways to install Minecraft launchers on various Linux distributions.


title: HISTORY
content:
Minecraft was created by Markus 'Notch' Persson and first released to the public in 2009, with its full release in 2011. While primarily known for its graphical user interface and cross-platform availability, server versions have always been capable of running headless on Linux servers, making it a popular choice for hosting multiplayer worlds. The game has consistently supported Linux users, primarily through its Java-based architecture, which allows its client and server JAR files to be executed directly, or via dedicated launchers provided by Mojang or the community.


title: TLDR
content:
<b>Start a Minecraft server and generate a world if it doesn't exist</b>`java -jar [path/to/server.jar] --nogui`<br><b>Set the minimum and maximum amount of memory a server is allowed to have (Note: Setting them the same prevents lag caused by heap scaling)</b>`java -Xms[1024M] -Xmx[2048M] -jar [path/to/server.jar] --nogui`<br><b>Start a server with a GUI</b>`java -jar [path/to/server.jar]`<br><b>Shut the server down</b>`stop`


title: SYNOPSIS
content:
<b>jj-parallelize</b> [<I>OPTIONS</I>] [<I>COMMAND_TEMPLATE</I> [<I>ARGUMENT_PLACEHOLDER</I>...]]<br><I>Or</I><br><b>jj-parallelize</b> [<I>OPTIONS</I>] &lt; <I>JOB_LIST_FILE</I><br><I>Or</I><br><I>generate_jobs</I> | <b>jj-parallelize</b> [<I>OPTIONS</I>]


title: PARAMETERS
content:
<b>-j <N>, --jobs <N></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the maximum number of commands to run concurrently. Defaults to the number of CPU cores.<br><br><b>-s <SEPARATOR>, --separator <SEPARATOR></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Defines the input record separator when reading jobs from stdin or a file. Default is newline.<br><br><b>-k, --keep-output-order</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Ensures that the output of the commands is printed in the same order as their input, buffering output if necessary.<br><br><b>-q, --quiet</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Suppresses command output, only showing errors or summaries.<br><br><b>--dry-run</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Prints the commands that would be executed without actually running them.<br><br><b>--retries <N></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Number of times to retry a failed command before giving up.<br><br><b>--fail-fast</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Exits immediately upon the first command failure, stopping all ongoing and pending jobs.<br><br><b>-v, --verbose</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Enables verbose output, showing more details about command execution and progress.<br><br>


title: DESCRIPTION
content:
jj-parallelize is conceptually designed as a utility to execute a set of commands or jobs in parallel, managing the concurrency level to efficiently utilize system resources. It aims to streamline workflows where multiple independent tasks need to be processed simultaneously. While its name suggests a link to the <I>just</I> command runner (often aliased <I>jj</I>), it is <B>not</B> a standard subcommand or a widely distributed tool within the <I>just</I> ecosystem or common Linux distributions. If it were to exist, it would likely function similarly to tools like <I>xargs -P</I> or GNU <I>parallel</I>, taking a list of commands or arguments and executing them up to a specified maximum number of concurrent processes. Its primary benefit would be accelerating operations by leveraging multi-core processors.


title: CAVEATS
content:
<b>jj-parallelize</b> is <B>NOT</B> a standard, widely distributed Linux command or a core feature of the <I>just</I> command runner. This analysis describes a <B>hypothetical</B> command based on its name, assuming it would provide parallel execution capabilities similar to tools like <I>xargs -P</I> or GNU <I>parallel</I>. If you encounter this command, it is likely a custom script, an internal tool, or a misinterpretation. For general-purpose parallel task execution on Linux, consider using <I>xargs -P</I> or GNU <I>parallel</I>. For parallelizing recipes within the <I>just</I> command runner, you typically use the <I>-j</I> or <I>--jobs</I> option with <I>just</I> itself (e.g., <I>just -j 4 recipe</I>), or structure your <I>Justfile</I> to call parallelizable external commands.


title: PARALLELISM IN JUSTFILES
content:
While <I>jj-parallelize</I> is not a standalone command, the <I>just</I> command runner (<I>jj</I>) natively supports parallel execution of its recipes. Users can run multiple recipes concurrently by invoking <I>just</I> with the <I>-j <N></I> or <I>--jobs <N></I> option (e.g., <I>just -j 8 build_all</I>). This allows <I>just</I> to execute independent recipes or steps in parallel, significantly speeding up build or task execution times. The specific implementation of parallelization depends on the external commands called by the recipes.


title: COMMON PARALLELIZATION PATTERNS
content:
For general shell scripting, common patterns for parallelization involve:<br>1. Using <I>xargs -P <N></I> to run a command with multiple arguments in parallel.<br>2. Employing GNU <I>parallel</I> for more advanced scenarios, including reading input from various sources, handling complex command structures, and managing output.<br>3. Backgrounding processes with <I>&</I> and waiting for them with <I>wait</I> in a shell script, often combined with a job slot counter to limit concurrency.


title: HISTORY
content:
As <b>jj-parallelize</b> is not a standard or widely documented Linux command, there is no public history of its development or usage. Its name suggests a potential connection to the <I>just</I> command runner (often aliased <I>jj</I>) and the concept of parallelization. It may exist as a custom script in specific environments or have been an experimental concept that was not broadly adopted.


title: DESCRIPTION
content:
The command <b>mailsy</b> is not a standard or commonly recognized utility in most Linux distributions. It does not appear in official documentation, man pages, or common package repositories.<br><br>It is highly likely that <b>mailsy</b> is either a typo for a different command (such as <b>mail</b> or <b>mailx</b>), a custom script, a very niche or deprecated tool, or an internal command specific to a particular environment. Therefore, a comprehensive analysis of its syntax, parameters, and functionality cannot be provided as it lacks a public, standardized definition.


title: CAVEATS
content:
This command is not found in standard Linux environments. Attempting to execute <b>mailsy</b> will typically result in a 'command not found' error unless a custom script or alias with this name has been specifically set up on the system.<br><br>Users looking for email-related command-line tools should refer to standard utilities like <b>mail</b>, <b>mailx</b>, <b>sendmail</b>, <b>mutt</b>, or <b>postfix</b>, which are widely available and well-documented.


title: VERIFICATION ON YOUR SYSTEM
content:
Before assuming <b>mailsy</b> is a valid command, users should verify its existence on their specific system using standard shell commands. For example, you can try: <br><i>which mailsy</i><br>or<br><i>type mailsy</i><br><br>If these commands return no output or an error indicating that the command was not found, it confirms that <b>mailsy</b> is not an executable in your system's PATH.


title: HISTORY
content:
There is no documented history for a standard Linux command named <b>mailsy</b> because it does not exist as a widely distributed or recognized utility. Its usage or development history would likely be limited to specific private projects or local system configurations where such a name might have been used, rather than a publicly maintained software.<br><br>Historically, common mail utilities on Linux have evolved from basic commands like <b>mail</b> to more complex Mail Transfer Agents (MTAs) and Mail User Agents (MUAs) such as <b>sendmail</b>, <b>postfix</b>, and <b>mutt</b>.


title: TLDR
content:
<b>Create an email address</b>`mailsy g`<br><b>Fetch emails (press <Enter> to open email in browser)</b>`mailsy m`<br><b>Show details about the account</b>`mailsy me`<br><b>Dispose the email address</b>`mailsy d`


title: SYNOPSIS
content:
<b>modinfo</b> [<I>options</I>] <I>module_name</I> | <I>filename</I><br><br><i>Note: Direct execution of 'modutil' is uncommon; its functionality is typically provided by tools like 'modinfo' from the kmod suite.</i>


title: PARAMETERS
content:
<b><b>-F</b> <I>field</I>, <b>--field</b>=<I>field</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Display only the value of the specified field for the module (e.g., `license`, `author`, `description`, `filename`).<br><br><b><b>-k</b> <I>kernel_version</I>, <b>--kernel</b>=<I>kernel_version</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specify the kernel version for which to get module information, rather than the running kernel.<br><br><b><b>-n</b>, <b>--null</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Use null characters to separate fields instead of newlines, useful for scripting output parsing.<br><br><b><b>-a</b>, <b>--author</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Equivalent to `<b>-F author</b>`: Show the author of the module.<br><br><b><b>-d</b>, <b>--description</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Equivalent to `<b>-F description</b>`: Show the description of the module.<br><br><b><b>-l</b>, <b>--license</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Equivalent to `<b>-F license</b>`: Show the license of the module.<br><br><b><b>-p</b>, <b>--parameters</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Equivalent to `<b>-F parm</b>`: Show the module parameters, their types, and descriptions.<br><br><b><b>-s</b>, <b>--summary</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Show a summary of common module information including author, description, license, dependencies, and parameters.<br><br><b><b>-V</b>, <b>--version</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Print the version of the utility and exit.<br><br><b><b>-h</b>, <b>--help</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Display a help message and exit.<br><br>


title: DESCRIPTION
content:
The `<b>modutil</b>` command is not a standalone executable on most modern Linux distributions. Historically, or in some specific contexts, `<b>modutil</b>` referred to a collection of utilities for kernel module operations, such as extracting module information or verifying module signatures. These functionalities are now primarily provided by the `<b>kmod</b>` package, which replaced the older `<b>module-init-tools</b>`. The most common functionality associated with `<b>modutil</b>`—dumping module metadata—is now performed by the `<b>modinfo</b>` command, a core part of the `<b>kmod</b>` suite. `<b>modutil</b>` may appear in older documentation or be used internally by certain scripts, but for general user interaction, `<b>modinfo</b>`, `<b>lsmod</b>`, `<b>insmod</b>`, `<b>rmmod</b>`, and `<b>modprobe</b>` are the primary commands to interact with kernel modules.


title: CAVEATS
content:
The `<b>modutil</b>` command is not typically available as a direct executable on most modern Linux systems. Its functions are absorbed into the `<b>kmod</b>` suite of utilities, particularly `<b>modinfo</b>`, `<b>lsmod</b>`, etc. Direct references to `<b>modutil</b>` are often found in older documentation, specific embedded systems, or internal scripts, and should generally be substituted with the appropriate `<b>kmod</b>` command for current systems.


title: COMMON USE CASES (VIA MODINFO)
content:
While `<b>modutil</b>` itself is rare, its functionalities are commonly accessed through `<b>modinfo</b>`. Here are some typical ways its successor, `<b>modinfo</b>`, is used:<br><br><b>Getting Comprehensive Module Information:</b><br><I>modinfo usb_storage</I><br>This command displays comprehensive information about the `usb_storage` kernel module, including its filename, license, author, description, dependencies, and parameters.<br><br><b>Querying Specific Fields:</b><br><I>modinfo -F license ath9k</I><br>Retrieves only the license information for the `ath9k` wireless driver module.<br><br><b>Checking Module Parameters:</b><br><I>modinfo -p nouveau</I><br>Lists all available parameters for the `nouveau` graphics driver module, along with their types and brief descriptions.


title: HISTORY
content:
`<b>modutil</b>`'s historical roots are tied to the `<b>module-init-tools</b>` package, which was the standard set of utilities for managing kernel modules on Linux systems. Over time, `<b>module-init-tools</b>` was largely replaced by the `<b>kmod</b>` project. `<b>kmod</b>` provides a more unified and robust framework for module management, consolidating various functionalities into its own set of subcommands and standalone utilities (like `<b>modinfo</b>`). Consequently, the standalone `<b>modutil</b>` command either ceased to exist as a direct executable or its functions were fully integrated into the `<b>kmod</b>` toolchain, making direct invocation unnecessary or deprecated for most users.


title: TLDR
content:
<b>Add a PKCS #11 module to a NSS database (e.g. a Firefox profile: $HOME/.mozilla/firefox/default-release)</b>`modutil -dbdir sql:[path/to/nss_database_directory] -add "[module_label]" -libfile [path/to/pkcs11_mod.so]`<br><b>List PKCS #11 modules in a NSS database</b>`modutil -dbdir sql:[path/to/nss_database_directory] -list`


title: TLDR
content:
<b>Enable [q]uiet mode and suppress normal test results</b>`chkrootkit -q`<br><b>Enable e[x]pert mode and produce additional outputs</b>`chkrootkit -x`<br><b>Enable [d]ebug mode to show all output</b>`chkrootkit -d`<br><b>Specify [e]xcluded files for some tests</b>`chkrootkit -e "[path/to/file]"`<br><b>Specify a directory as the [r]oot for testing (e.g. mounted ext drives)</b>`chkrootkit -r [path/to/directory]`<br><b>Ignore [n]fs-mounted directories</b>`chkrootkit -n`<br><b>Invoke [T]ests and ignore specific filesystem types</b>`chkrootkit -T [filesystemtype]`<br><b>Generate [l]ist of available tests</b>`chkrootkit -l`


title: PARAMETERS
content:
<b><I>REVISION</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;The target commit to edit. If omitted, it defaults to the working copy's parent commit (the commit your working copy is currently based on). This allows you to edit the immediately preceding commit conveniently.<br><br><b><b>-r, --revision <I>REVISION</I></b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Explicitly specifies the revision of the commit to edit. This option serves the same purpose as the positional <I>REVISION</I> argument.<br><br><b><b>-p, --parent</b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;A convenience option to explicitly indicate that you want to edit the parent of the current working-copy commit. This is often the default behavior if no revision is specified, making it clear you're targeting the immediate ancestor.<br><br><b><b>-m, --message <I>MESSAGE</I></b></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets the commit message for the edited commit. Note that this message will be ignored if the commit already has a non-empty description.<br><br>


title: DESCRIPTION
content:
The <b>jj edit</b> command is a fundamental subcommand of the Jujutsu (jj) version control system, designed for easily modifying the contents of any existing commit, not just the latest one. Unlike Git's `git commit --amend` which primarily targets the head commit, <b>jj edit</b> allows you to "check out" an arbitrary commit into your working directory. Once the commit's state is loaded, you can make any desired changes to the files, add new files, or remove existing ones. After making your modifications, you would typically use `jj commit` (or implicitly, `jj` will create a new commit if you make changes and then run another `jj` command that expects a clean working directory). This powerful feature enables intuitive history rewriting without complex `rebase -i` operations, as <b>jj</b> treats history as mutable by default, creating new versions of commits instead of directly altering them in place.


title: CAVEATS
content:
Using <b>jj edit</b> modifies history by creating new commit IDs for any changes made, effectively replacing the original commit in the history graph. While Jujutsu's design makes this less disruptive than in Git, care should be taken when collaborating, as published commits should generally be considered immutable. Users should understand Jujutsu's concept of mutable history and how it differs from Git's immutable commits.


title: TYPICAL WORKFLOW
content:
The usual workflow involves running `jj edit <revision>`, which updates your working directory to the state of that commit. You then make your desired file changes using your favorite editor or IDE. After changes are complete, you can continue with other `jj` commands (like `jj commit`, `jj next`, or `jj prev`), and <b>jj</b> will automatically create a new commit version incorporating your changes and rebase subsequent commits on top of it. If you wish to discard changes, simply run `jj restore --working-copy`.


title: MUTABILITY AND CONFLICTS
content:
<b>jj</b> embraces a mutable history model, where commits are not immutable objects. When you edit a commit with <b>jj edit</b> and make changes, a *new* commit is created that incorporates your modifications, and all subsequent commits are automatically rebased onto this new commit. This makes history rewriting much more seamless. If conflicts arise during the rebase process (e.g., if a subsequent commit modified the same lines you just edited), <b>jj</b> will pause and provide tools like `jj resolve` to help you resolve them.


title: HISTORY
content:
<b>jj</b> (Jujutsu) is a relatively new distributed version control system developed by Google, first publicly released around 2022. It aims to offer a more user-friendly and powerful alternative to Git, especially in handling history rewriting. The <b>jj edit</b> command is a core component of this vision, providing a streamlined way to interactively modify past commits, addressing a common pain point in Git workflows that often required complex `git rebase --interactive` operations.


title: PARAMETERS
content:
<b><i><b>--revision</b></i>, <i><b>-r</b></i> <<i><b>REV</b></i>></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the commit to describe. If omitted, the command defaults to operating on the current working-copy commit.<br><br><b><i><b>--message</b></i>, <i><b>-m</b></i> <<i><b>MESSAGE</b></i>></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Provides the commit message directly on the command line. If this option is used, the configured editor will not be opened unless <i><b>--interactive</b></i> is also specified.<br><br><b><i><b>--from-file</b></i>, <i><b>-F</b></i> <<i><b>FILE</b></i>></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Reads the commit message from a specified file. Similar to <i><b>--message</b></i>, it bypasses opening the editor unless <i><b>--interactive</b></i> is used.<br><br><b><i><b>--interactive</b></i>, <i><b>-i</b></i>, <i><b>--edit</b></i>, <i><b>-e</b></i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Forces the command to open the editor, even if a commit message has been provided via the <i><b>--message</b></i> or <i><b>--from-file</b></i> options. This is useful for reviewing or making minor edits to a pre-supplied message.<br><br><b><i><b>--print</b></i>, <i><b>-p</b></i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Prints the new commit description to standard output after it has been successfully applied.<br><br><b><i><b>--tool</b></i> <<i><b>TOOL</b></i>></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies a particular editor tool to use for modifying the commit message. This option overrides any editor configured in <i><b>jj</b></i>'s settings or system defaults.<br><br><b><i><b>--reset-author</b></i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Resets the author of the commit to the current user's identity and the current timestamp, overwriting the original author information of the commit.<br><br>


title: DESCRIPTION
content:
<i><b>jj describe</b></i> is a fundamental command within the <br>Jujutsu (<i><b>jj</b></i>) version control system. Its primary purpose <br>is to modify the commit message (description) and, optionally, <br>the author information of a specific commit. <br><br>By default, when invoked without a target revision, it operates <br>on the current working copy commit. When no message is provided <br>via command-line options (<i><b>-m</b></i> or <i><b>-F</b></i>), <i><b>jj describe</b></i> opens <br>an editor (configured via <i><b>jj</b></i> settings or system defaults). <br>This editor is pre-populated with the existing commit message, <br>allowing users to refine, correct, or expand upon the commit's <br>context. <br><br>This command is crucial for maintaining a clear and accurate <br>commit history, fixing typos in past messages, or adding <br>more detailed explanations. It aligns perfectly with Jujutsu's <br>design philosophy of easily mutable local history, making <br>commit message amendments a simple and integrated part of <br>the development workflow.


title: CAVEATS
content:
While <i><b>jj</b></i> simplifies rewriting history, altering a commit that has already been published and built upon by collaborators can still lead to conflicts for others if not properly coordinated.<br><br>The command relies on a correctly configured editor. If no editor is found or specified, the command may fail when interaction is required.


title: EDITOR BEHAVIOR
content:
When <i><b>jj describe</b></i> opens an editor, it typically populates it <br>with the commit's current message. Users can then modify, <br>add to, or replace the content. Lines starting with '<i><b>#</b></i>' <br>within the editor are treated as comments and are ignored <br>when the final commit message is saved.


title: DEFAULT TARGET COMMIT
content:
By default, if no revision is specified, <i><b>jj describe</b></i> operates <br>on the working copy commit. This allows for quick iteration <br>and refinement of the most recent changes made by the user.


title: HISTORY
content:
The <i><b>jj describe</b></i> command is an integral component of the <br>Jujutsu (<i><b>jj</b></i>) version control system. Jujutsu was conceived to <br>provide a more intuitive and powerful approach to version control <br>compared to traditional systems like Git. It emphasizes local, <br>mutable history, making operations such as rewriting commit <br>messages, which <i><b>jj describe</b></i> primarily facilitates, straightforward <br>and atomic. Designed to streamline common version control <br>workflows, <i><b>jj describe</b></i> plays a crucial role in enabling users to <br>easily refine and organize their commit history.


title: SEE ALSO
content:
<i><b>jj commit</b></i>(1), <i><b>jj new</b></i>(1), <i><b>jj rebase</b></i>(1), <i><b>jj log</b></i>(1)


title: TLDR
content:
<b>Update the description of the current change</b>`jj [[desc|describe]]`<br><b>Update the description of given revsets</b>`jj [[desc|describe]] [revsets]`<br><b>Update the description to the given message</b>`jj [[desc|describe]] [[-m|--message]] [message]`


title: PARAMETERS
content:
<b>create</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Creates an empty Elasticsearch keystore file at the default or specified path.<br><br><b>add &lt;setting_name&gt;</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Adds a new sensitive setting to the keystore. Use <i>-x</i> to prompt for the value securely from the command line, or <i>--force</i> to overwrite an existing setting. Example: <i>elasticsearch-keystore add s3.client.default.access_key -x</i><br><br><b>list</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Lists all setting names currently stored in the keystore, without revealing their values.<br><br><b>remove &lt;setting_name&gt;</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Removes a specified setting from the keystore.<br><br><b>show &lt;setting_name&gt;</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays the value of a specified setting. Note: This command cannot display the values of secure settings that were added using the <i>-x</i> option for security reasons.<br><br><b>passwd</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets or changes the password for an encrypted keystore. If the keystore is not encrypted, this command will add password protection.<br><br><b>upgrade</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Upgrades the keystore file to the latest compatible format, if an older format is detected.<br><br>


title: DESCRIPTION
content:
The <b>elasticsearch-keystore</b> command-line utility is an essential tool for managing sensitive settings in Elasticsearch, such as passwords, cloud credentials, and other confidential information. By using a keystore, administrators can avoid storing these values in plain text within the <i>elasticsearch.yml</i> configuration file, significantly enhancing security. The keystore itself is an encrypted file, protecting its contents from unauthorized access. This utility allows users to add, remove, list, and manage the secure settings, ensuring that only authorized Elasticsearch processes can access the sensitive data during operation. Changes made with this command typically require a restart of the Elasticsearch node to take effect.


title: CAVEATS
content:
<b><br>Security Best Practices:</b><br>It is highly recommended to protect your keystore with a password, especially in production environments. Without a password, anyone with file system access can retrieve secure settings.<br><br><b>Node Restart:</b><br>After making any changes to the keystore (add, remove, passwd), the Elasticsearch node(s) must be restarted for the changes to take effect.<br><br><b>Backup:</b><br>Always back up your <i>elasticsearch.keystore</i> file before making significant changes or upgrading Elasticsearch.


title: KEYSTORE LOCATION
content:
By default, the <i>elasticsearch.keystore</i> file is located in the Elasticsearch configuration directory (<i>$ES_HOME/config</i>). This location can be overridden using the <i>ES_PATH_CONF</i> environment variable.


title: SECURE SETTINGS VS. REGULAR SETTINGS
content:
The keystore can store both 'secure settings' (e.g., passwords, API keys) and 'regular settings' (e.g., paths, non-sensitive string values). Secure settings are typically added with the <i>-x</i> option, ensuring their values are never exposed on the command line or in logs, and cannot be displayed via the <i>show</i> command. Regular settings added without <i>-x</i> can be displayed.


title: HISTORY
content:
The concept of an Elasticsearch keystore and the <b>elasticsearch-keystore</b> utility were introduced with Elasticsearch version 5.0.0. Its primary purpose was to provide a secure method for storing sensitive configuration settings, moving away from plain-text storage in <i>elasticsearch.yml</i> and aligning with modern security practices for application configuration.


title: TLDR
content:
<b>Create a new keystore (not password-protected)</b>`elasticsearch-keystore create`<br><b>Create a new password-protected keystore</b>`elasticsearch-keystore create -p`<br><b>Add a setting interactively</b>`elasticsearch-keystore add [setting_name]`<br><b>Add a setting from stdin</b>`echo "[setting_value]" | elasticsearch-keystore add --stdin [setting_name]`<br><b>Remove a setting from the keystore</b>`elasticsearch-keystore remove [setting_name]`<br><b>Change the keystore password</b>`elasticsearch-keystore passwd`<br><b>List all settings stored in the keystore</b>`elasticsearch-keystore list`<br><b>Upgrade the keystore format (after an Elasticsearch upgrade)</b>`elasticsearch-keystore upgrade`


title: PARAMETERS
content:
<b>-c, --char <CHARACTER></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the character to use for the box borders (e.g., '#', '*', '='). Defaults to a simple hash (#) character.<br><br><b>-p, --padding <NUMBER></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets the number of spaces for internal padding between the text and the box border. Defaults to 1.<br><br><b>-t, --title <STRING></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Adds a title string, centered, at the top border of the box.<br><br><b>-w, --width <NUMBER></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Forces the box to a specific fixed width. Text might be wrapped or truncated to fit.<br><br><b>-h, --help</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays a brief help message and exits.<br><br>


title: DESCRIPTION
content:
The `boxxy` command is a <I>hypothetical</I> utility designed to easily create text-based boxes around content in a terminal. It aims to enhance readability and visual organization of command-line output. Users could specify various attributes such as the border characters, internal padding, and an optional title for the box. This flexibility allows for diverse visual effects, from simple outlines to decorative frames. It's envisioned to process input either from standard input (piped data) or directly from provided command-line arguments, making it versatile for highlighting messages, formatting log entries, or adding structure to interactive scripts. As a conceptual tool, its implementation would require custom scripting or development, as it is not a standard component of any major Linux distribution.


title: CAVEATS
content:
This command is <I>hypothetical</I> and does not exist as a standard utility in common Linux distributions. Its behavior and availability would depend entirely on a custom implementation. Users seeking similar functionality might achieve it through shell scripting or existing text processing tools.


title: USAGE EXAMPLES
content:
Illustrative examples demonstrating the versatile application of the `boxxy` command to format terminal output with different options.<br><br><b>echo</b> "Hello Linux World!" | <b>boxxy</b><br><br><b>boxxy</b> <I>-c='*' -p=2</I> "Important Announcement for Users"<br><br><b>boxxy</b> <I>-t="Warning" -c='!' -w=40</I> "System critical error detected. Please review logs."<br><br><b>boxxy</b> <I>--char='=' --padding=0</I> "Text without padding"


title: HISTORY
content:
The `boxxy` command is a <I>fictional</I> utility conceptualized for this analysis. It draws inspiration from the idea of enhancing terminal output readability and presentation. In a real-world context, similar text-boxing capabilities are often achieved through custom shell functions, `awk` scripts, or `perl` one-liners. Its name, while coincidentally reminiscent of the internet meme 'Boxxy', primarily suggests its core function: enclosing text within a visual 'box' structure.


title: TLDR
content:
<b>Run a program with file redirections defined in ~/.config/boxxy/boxxy.yaml</b>`boxxy [program]`<br><b>Scan your home directory for rule suggestions</b>`boxxy scan`<br><b>Trace what files a program touches and save a report in boxxy-report.txt in the current directory</b>`boxxy [[-t|--trace]] [program]`<br><b>Pass a redirection rule directly on the terminal</b>`boxxy [[-r|--rule]] [path/to/file_or_directory]:[path/to/redirection]:[file|directory] [program]`<br><b>View the config file</b>`boxxy config`<br><b>Display help</b>`boxxy -h`


title: PARAMETERS
content:
<b>fetch</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Synchronizes the local Jujutsu repository with changes from configured Git remotes. This pulls new commits and updates Git remote-tracking branches within Jujutsu's view, allowing you to see and integrate the latest upstream changes.<br><br><b>push</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Pushes local Jujutsu commits to a specified Git remote. This command typically exports the current branch or designated changesets, making them available in the Git repository. Common options include <I>--branch</I> (to specify branches to push) and <I>--force</I> (to force-push, potentially overwriting remote history).<br><br><b>export</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Explicitly exports Jujutsu commits to local Git refs (e.g., branches or tags) without interacting with a remote. Useful for inspecting the Git view of Jujutsu's state locally, creating specific local Git branches from Jujutsu, or for more advanced integration scenarios.<br><br><b>import</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Imports Git refs (like branches or tags) from the local Git repository into Jujutsu's internal state. This makes Git-managed commits accessible and manageable within Jujutsu, often used when migrating an existing Git repository to Jujutsu.<br><br><b>remote</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Manages Git remotes configured for the Jujutsu repository. This subcommand itself has further subcommands like <I>add</I> (to add a new remote), <I>remove</I> (to delete a remote), and <I>list</I> (to display configured remotes), mirroring Git's remote management functionalities.<br><br><b>[common options]</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Many <I>jj git</I> subcommands, especially <I>push</I> and <I>fetch</I>, accept common Git-like options such as <I>--branch &lt;branches&gt;</I> (to specify branches), <I>--force</I> (to force operations), and <I>--dry-run</I> (to show what would happen without making changes).<br><br>


title: DESCRIPTION
content:
The <I>jj git</I> command group within the <I>Jujutsu</I> (jj) version control system provides essential functionalities for interacting with traditional <I>Git</I> repositories. It serves as a crucial bridge, enabling users to leverage Jujutsu's powerful features, such as stacked changes and mutable history, while seamlessly collaborating with teams and systems that primarily rely on Git. This suite of subcommands facilitates fetching changes from Git remotes, pushing local Jujutsu commits to Git branches, and managing the synchronization between Jujutsu's internal state and Git's commit graph. By integrating import and export capabilities, <I>jj git</I> ensures compatibility with existing Git workflows and infrastructure, simplifying adoption and improving development fluidity for mixed environments.


title: CAVEATS
content:
Understanding the mapping between Jujutsu's stacked changes and Git's linear history is crucial, as is managing potential conflicts during synchronization. While <I>jj git</I> aims for seamless interoperability, advanced Git operations or non-standard repository structures might require careful handling. Users should be aware that Git's state is a projection of Jujutsu's, not the other way around.


title: SYNCHRONIZATION MODEL
content:
<I>jj git</I> operates on a principle of maintaining a clear separation between Jujutsu's internal commit graph (with its mutable history and stacked changes) and the traditional Git repository's state. When you <I>fetch</I>, Jujutsu updates its view of Git's remote-tracking branches. When you <I>push</I>, Jujutsu carefully exports its selected commits to Git branches, translating its internal representation to a Git-compatible one. This design allows Jujutsu to offer its unique features while still providing a well-defined pathway for Git interaction.


title: CONFIGURATION OF REMOTES
content:
Git remotes and their URLs are configured within Jujutsu using the <I>jj git remote</I> subcommand, or by directly editing the Jujutsu configuration file. This mirrors how Git remotes are managed, ensuring familiar setup and interaction with upstream and downstream repositories.


title: JUJUTSU BRANCHES VS. GIT BRANCHES
content:
It's important to distinguish between Jujutsu's concept of branches (managed by <I>jj branch</I>) and Git's branches. While both are used to track lines of development, <I>jj git push</I> and <I>jj git export</I> are the primary commands used to explicitly map and synchronize Jujutsu-managed branches to corresponding Git branches for collaboration.


title: HISTORY
content:
The <I>jj git</I> subcommand group is a fundamental component of the <I>Jujutsu</I> (jj) SCM, which began active development around 2020-2021 as a modern alternative to Git with a focus on usability and powerful commit graph manipulation. From its early stages, interoperability with Git was a core design principle, recognizing Git's widespread adoption. The <I>git</I> subcommand was thus implemented to ensure that Jujutsu users could easily work with existing Git repositories and collaborate with Git users, making the transition to Jujutsu more practical for teams and individuals.


title: TLDR
content:
<b>Create a new Git backed repository</b>`jj git init`<br><b>Create a new repository backed by a clone of a Git repository</b>`jj git clone [source]`<br><b>Fetch from a Git remote</b>`jj git fetch`<br><b>Push all tracked bookmarks to Git remote</b>`jj git push`<br><b>Push given bookmark to Git remote</b>`jj git push [[-b|--bookmark]] [bookmark]`


title: DESCRIPTION
content:
The <b>gdm-restart</b> command is used to restart the GNOME Display Manager (GDM) service. GDM is a crucial component of the GNOME desktop environment, acting as the graphical login manager that handles user authentication, displays the login screen, and starts user sessions.<br><br>Restarting GDM effectively terminates all active graphical user sessions, returning the system to the login prompt. This action is commonly employed for troubleshooting display or login-related issues, applying changes to GDM's configuration files (like <i>/etc/gdm3/custom.conf</i> or <i>/etc/gdm/custom.conf</i>), or simply to force a new login screen without requiring a complete system reboot. Since it manages system-level services, executing this command typically requires administrative privileges or interaction with a system service manager like <b>systemctl</b>.


title: CAVEATS
content:
Restarting GDM will immediately terminate all active graphical user sessions, leading to the loss of any unsaved work. Users should ensure all applications are closed and data saved before executing this command.<br><br>It almost always requires root or <b>sudo</b> privileges, as it manipulates a system-level service. The exact service name might vary between distributions (e.g., <i>gdm.service</i> or <i>gdm3.service</i>), and the method of execution might also differ (e.g., direct script or a call to <b>systemctl</b>).


title: COMMON IMPLEMENTATION
content:
On most modern Linux distributions using <b>systemd</b>, the action of restarting GDM is typically achieved by issuing the command <b>sudo systemctl restart gdm.service</b> or <b>sudo systemctl restart gdm3.service</b> depending on the specific GDM package name used by the distribution (e.g., Fedora uses <i>gdm</i>, Debian/Ubuntu uses <i>gdm3</i>). The <b>gdm-restart</b> command, if it exists, is often a wrapper script that executes one of these <b>systemctl</b> commands internally.


title: IMPACT ON USER SESSIONS
content:
It is crucial to understand that restarting GDM is a drastic action for active graphical users. It will immediately terminate all currently running graphical desktop sessions, causing any unsaved work in applications to be lost. Users will be returned to the graphical login screen, where they can log in again to start a new session.


title: HISTORY
content:
The concept of restarting a display manager like GDM has been integral to managing graphical environments since the early days of X Window System display managers (like <i>XDM</i>). GDM itself was developed specifically for the GNOME desktop environment, providing a graphical login interface.<br><br>While the exact <b>gdm-restart</b> command might not have a distinct, long development history as a standalone utility, its functionality has been consistently achieved through various system management tools. In modern Linux distributions, its operation is primarily handled by <b>systemd</b>, which superseded older <i>SysVinit</i> or <i>Upstart</i> systems for service management. This transition streamlined the process of starting, stopping, and restarting system services, including GDM.


title: PARAMETERS
content:
<b>--revision &lt;REVISION&gt;, -r &lt;REVISION&gt;</b><br>&nbsp;&nbsp;&nbsp;&nbsp;The commit to squash into its parent. If not specified, it defaults to the current working copy's commit.<br><br><b>--message &lt;MESSAGE&gt;, -m &lt;MESSAGE&gt;</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Use the given text as the commit message for the new parent commit. If not specified and not interactive, the original parent's message is retained.<br><br><b>--interactive, -i</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Open an editor to modify the commit message of the new parent commit. This allows for combining or editing messages from both the squashed and parent commits.<br><br><b>--tool &lt;TOOL&gt;</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specify the external tool (e.g., editor) to use for interactive operations.<br><br><b>--ignore-unstaged</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Do not include any unstaged changes from the working copy into the resulting parent commit. By default, associated unstaged changes are also squashed.<br><br><b>--allow-empty</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Allow the parent commit to become empty (have no changes) after the squash operation. By default, <i>jj squash</i> prevents creating an empty commit unless it was already empty.<br><br>


title: DESCRIPTION
content:
<i>jj squash</i> is a fundamental command in the Jujutsu (<i>jj</i>) version control system, designed to simplify history rewriting. Its primary function is to combine the changes (diff) of a specified commit into its direct parent commit. This operation effectively moves the content and message of the target commit into its parent, subsequently abandoning the original (child) commit. <br><br>This command is commonly used to clean up commit history, for example, to consolidate small fix-up commits, trivial changes, or work-in-progress modifications into a more substantial, logical parent commit. It helps in maintaining a linear, readable, and clean commit graph, which is crucial for code review processes and project maintainability. Unlike <i>jj amend</i>, which typically modifies the current commit, <i>jj squash</i> specifically focuses on integrating a commit's changes into its parent, making it ideal for tidying up commit sequences from bottom-up.


title: CAVEATS
content:
<i>jj squash</i> modifies history, which can affect collaborators if changes have been pushed and shared. While Jujutsu's mutable history model is designed for safety and ease of use, it's still good practice to coordinate with team members.<br><br>The squashed commit is abandoned, meaning it's no longer directly reachable in the visible history. However, it can be recovered using commands like <i>jj log --abandoned</i> followed by <i>jj restore</i> or <i>jj unabandon</i>.<br><br>This command typically operates on non-merge commits. Squashing a merge commit might have complex or unexpected behavior, or be disallowed.


title: DEFAULT TARGET
content:
When no <i>REVISION</i> is specified, <i>jj squash</i> defaults to squashing the current working copy's commit into its immediate parent. This is a common use case for refining the commit you are currently working on.


title: UNSTAGED CHANGES
content:
By default, any unstaged changes associated with the commit being squashed are also moved into the parent commit. The <i>--ignore-unstaged</i> flag provides granular control over this behavior, allowing you to keep unstaged changes separate if desired.


title: COMMIT MESSAGE HANDLING
content:
If neither the <i>--message</i> nor <i>--interactive</i> flags are used, the resulting parent commit will retain its original commit message. To combine or modify messages, either provide a new message directly or use the interactive editor.


title: HISTORY
content:
Jujutsu (<i>jj</i>) is a modern distributed version control system developed by Google, aiming to provide a more intuitive and powerful alternative to Git, especially concerning history manipulation. The <i>jj squash</i> command is a core component of <i>jj</i>'s design philosophy, making history rewriting operations simple and explicit. It addresses a common need in development workflows for cleaning up commit history before sharing, similar to Git's interactive rebase with 'fixup' or 'squash' actions, but integrated as a first-class, user-friendly command within Jujutsu's powerful mutable history model.


title: TLDR
content:
<b>Move all changes from current revision to its parent</b>`jj squash`<br><b>Move all changes from given revision to its parent</b>`jj squash [[-r|--revision]] [revset]`<br><b>Move all changes from given revision(s) to given other revision</b>`jj squash [[-f|--from]] [revsets] [[-t|--into]] [revset]`<br><b>Interactively choose which parts to squash</b>`jj squash [[-i|--interactive]]`


title: TLDR
content:
<b>Start Midnight Commander</b>`mc`<br><b>Start Midnight Commander in black and white</b>`mc [[-b|--nocolor]]`


title: PARAMETERS
content:
<b><I>PATHS</I>...</b><br>&nbsp;&nbsp;&nbsp;&nbsp;One or more paths to files or directories to restore. If no paths are specified, all files are considered for restoration.<br><br><b>--from <I>REVISION</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the source revision from which to copy the file content. Defaults to the working copy's parent commit if not specified.<br><br><b>--to <I>REVISION</I></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the target revision into which the files will be restored. Defaults to the working copy.<br><br><b>--allow-unmatched</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Prevents the command from returning an error if some of the specified paths do not match any files in the source revision.<br><br><b>-n, --dry-run</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Performs a dry run, showing which files would be affected without actually making any changes.<br><br><b>-h, --help</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays a help message for the `jj restore` command.<br><br>


title: DESCRIPTION
content:
The `jj-restore` command in Jujutsu is used to copy specific files or directories from one revision's tree state to another, typically to the working copy. It is analogous to `git restore`, allowing users to undo local modifications, restore deleted files, or bring back files from a past version.<br><br>By default, `jj-restore` copies file content from the parent of the current working copy commit into the working copy itself. This effectively reverts any local changes made to those files since the last commit. Users can specify a different source revision using the `--from` option, enabling the restoration of files from any commit in the repository's history, or even from the working copy itself if desired (e.g., to restore a deleted file from the working copy back into the working copy from a source commit).<br><br>The `--to` option allows specifying the target revision where the files should be restored. By default, this is the working copy. When paths are provided, only those specific files or directories are affected. If no paths are given, the entire tree is restored from the specified source to the destination. `jj-restore` operates directly on the files and does not involve a separate staging area, aligning with Jujutsu's design philosophy of a mutable history.


title: CAVEATS
content:
Using `jj-restore` can overwrite uncommitted local changes in your working copy if the target is the working copy. Always ensure you understand the source and target revisions to avoid unintended data loss. Jujutsu does not have a traditional staging area, so changes are applied directly.


title: HISTORY
content:
Jujutsu (jj) is a relatively new and experimental version control system designed to offer a simpler and more intuitive interface than Git, focusing on a mutable history and rebase-first workflows. The `jj-restore` command is a fundamental part of its core functionality, providing a direct way to manage file states, mirroring essential capabilities found in more established VCS tools from its early development.


title: TLDR
content:
<b>Restore files from a revision into another revision</b>`jj restore [[-f|--from]] [revset] [[-t|--into]] [revset] [filesets]`<br><b>Undo the changes in a revision as compared to the merge of its parents</b>`jj restore [[-c|--changes-in]] [revset] [filesets]`<br><b>Interactively choose what parts to restore</b>`jj restore [[-f|--from]] [revset] [[-t|--into]] [revset] [[-i|--interactive]]`


title: SYNOPSIS
content:
The `freeramdisk` command was typically invoked with the path to the RAM disk device.<br><i>Syntax (historical/illustrative):</i><br><b>freeramdisk</b> <i>/dev/ramN</i>


title: PARAMETERS
content:
<b><i>/dev/ramN</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;The device node corresponding to the RAM disk (e.g., <i>/dev/ram0</i>, <i>/dev/ram1</i>) whose memory pages were to be freed. No standard options were typically associated with this command.<br><br>


title: DESCRIPTION
content:
The `freeramdisk` command is an <b>obsolete</b> utility historically used in early Linux kernel versions (primarily 2.0.x and 2.2.x) to explicitly mark memory pages associated with a kernel RAM disk device (e.g., <i>/dev/ram0</i>) as free, allowing them to be reused by the system. In older Linux kernels, RAM disks were typically managed by the `ramdisk` kernel module, and their memory might not have been automatically released upon unmounting or system shutdown as efficiently as modern memory management. This command provided a way to reclaim that memory manually after a RAM disk was no longer needed. It was often employed in early boot scripts (e.g., in `initrd`) before transitioning to the root filesystem.<br><br><b>Modern Linux distributions no longer include or require `freeramdisk`.</b> Its functionality has been superseded by more advanced and automatic memory management within the kernel, particularly through the use of `tmpfs` and `ramfs` filesystems, which automatically handle memory allocation and deallocation for in-memory storage, and the `brd` (block ramdisk) module for block-device-based RAM disks. Memory used by these modern in-memory filesystems or block devices is automatically freed when they are unmounted or removed.


title: CAVEATS
content:
This command is <b>obsolete</b> and <b>not available</b> in modern Linux distributions. Attempting to run `freeramdisk` on a contemporary system will result in a "command not found" error. Its functionality has been entirely absorbed and improved upon by the kernel's built-in memory management and modern in-memory filesystem types like `tmpfs` and `ramfs`. Users should use `tmpfs` for temporary filesystems residing in RAM, and memory will be automatically managed.


title: MODERN ALTERNATIVES
content:
For creating and managing RAM-based storage in modern Linux, consider using `tmpfs` for file system-like storage in RAM, or the `brd` kernel module (block ramdisk) for block device-like storage. `tmpfs` is a virtual memory filesystem that stores its contents in virtual memory (RAM and swap). It is created using `mount -t tmpfs -o size=... tmpfs /mnt/ramdisk`. Memory is automatically freed upon unmount. `ramfs` is a simpler, older in-memory filesystem that doesn't support swapping, primarily used for very small, ephemeral data.


title: HISTORY
content:
The `freeramdisk` utility was part of the early Linux toolset, particularly prominent during the 2.0.x to 2.2.x kernel series. It addressed a specific need for explicit memory reclamation from RAM disks when kernel memory management for these devices was less sophisticated. As the Linux kernel evolved, particularly with the introduction of virtual filesystems like `tmpfs` (which became standard around kernel 2.4) and enhancements to the block device layer, the need for a separate `freeramdisk` command diminished. Its functionality was integrated directly into the kernel's handling of RAM-based storage, leading to its deprecation and eventual removal from common Linux distributions.


title: PARAMETERS
content:
<b>-r, --revisions <REVISIONS>...</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the commit(s) to be abandoned. If omitted, the working copy's current commit is abandoned. Multiple revisions can be provided.<br><br><b>--no-abandon-working-copy</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Prevents the working-copy commit from being abandoned if it is among the specified revisions. Instead, a new working-copy commit will be created on a non-abandoned ancestor.<br><br>


title: DESCRIPTION
content:
<i>jj abandon</i> marks one or more commits as "abandoned." In Jujutsu, abandoned commits are conceptually removed from the visible history of a branch, making them unlisted by default in commands like <i>jj log</i>. However, the commit data itself is not immediately deleted from the repository. This non-destructive nature allows for later recovery if needed.<br><br>Abandoning is useful for cleaning up working history, removing experimental changes, or correcting mistakes without permanently losing the work. When a commit is abandoned, all its descendants are also implicitly abandoned, ensuring graph consistency. This command is often used to tidy up the commit graph, offering a unique approach compared to other version control systems.


title: CAVEATS
content:
<b>While commits are not physically deleted</b>, they become invisible by default in most <i>jj</i> commands. Recovery requires knowing their commit hash, which can be challenging if not explicitly noted.<br><b>Abandoning a commit also implicitly abandons all its descendants</b>, which can have cascading effects on your commit history.<br>There is <b>no direct "undo" command</b> for <i>jj abandon</i>. Recovery relies on commands like <i>jj restore</i> or <i>jj new</i> with the old commit ID.<br>Can affect concurrent work if others are building on the abandoned commits, as their history will no longer be visible by default.


title: RECOVERY OF ABANDONED COMMITS
content:
Abandoned commits are not permanently deleted from the repository. They are tracked in the obsolescence log (viewable with <i>jj obslog</i>) and can be recovered by referring to their commit hash using commands like <i>jj new &lt;hash&gt;</i> or <i>jj restore &lt;hash&gt;</i>. This provides a safety net not easily available in other VCS systems after discarding changes.


title: IMPACT ON DESCENDANTS
content:
When you abandon a commit, all its child commits (descendants) are also implicitly marked as abandoned. This ensures the consistency of the commit graph. If you intend to preserve certain descendants, you should typically use <i>jj rebase</i> to move them onto a different, non-abandoned parent <b>before</b> performing the abandon operation.


title: HISTORY
content:
Jujutsu (<i>jj</i>) is a relatively new version control system designed to address some pain points of Git, particularly around mutable history and commit identification. <i>jj abandon</i> is a core operation reflecting <i>jj</i>'s philosophy of making history explicit and manageable. Unlike Git's <i>git reset --hard</i> which discards commits (making them subject to garbage collection), <i>jj abandon</i> explicitly marks commits as obsolete but keeps their data accessible via the <i>obslog</i> and by hash, allowing for easier recovery and a more robust history model. Its development is ongoing as part of the <i>jj</i> project.


title: TLDR
content:
<b>Abandon revisions specified by given revsets (e.g. B::D, A..D, B|C|D, etc.)</b>`jj abandon [revsets]`<br><b>Abandon revisions, without deleting their bookmarks and moving them to the parent revisions instead</b>`jj abandon --retain-bookmarks [revsets]`<br><b>Abandon revisions, without modifying the contents of their children</b>`jj abandon --restore-descendants [revsets]`


title: PARAMETERS
content:
<b>-m, --message &lt;MESSAGE&gt;</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets the initial commit message. This message will be used as the commit's summary line.<br><br><b>-d, --description &lt;DESCRIPTION&gt;</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Sets a longer description for the commit, which appears below the summary line. This is analogous to the body of a Git commit message.<br><br><b>-i, --interactive</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Launches an interactive session (using a diff editor) to allow you to select which changes (hunks) should be included in the commit. This provides granular control over what gets committed.<br><br><b>-e, --empty</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Forces the creation of a new, empty commit, even if there are uncommitted changes in the working directory. If there are changes, they will not be included in this new empty commit but will remain in the working copy.<br><br><b>-r, --revision &lt;REVISION&gt;</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the revision to commit on top of. By default, <i>jj-commit</i> operates on the current working copy commit. This option allows you to create or amend a commit other than the working copy.<br><br><b>--tool &lt;TOOL&gt;</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Specifies the external tool to use for interactive operations (e.g., when <i>--interactive</i> is used). Examples include <i>jj-diff-editor</i> or other configured diff tools.<br><br>


title: DESCRIPTION
content:
<i>jj-commit</i> is a fundamental command within the <b>Jujutsu (jj)</b> distributed version control system. Its primary function is to record changes from your working directory into a commit. <br><br>Unlike traditional Git workflows, <i>jj-commit</i> operates directly on the 'working copy commit'—the specific commit currently checked out in your workspace. If there are uncommitted changes (modifications to tracked files or new untracked files), <i>jj-commit</i> will <b>amend</b> this working copy commit by incorporating those changes. If the working copy is clean (no uncommitted changes), <i>jj-commit</i> will create a <b>new, empty commit</b> on top of it. <br><br>This command simplifies the commit process by implicitly including all changes by default (similar to <i>git commit -a</i>), reducing the need for an explicit staging area. You can provide a commit message and an optional extended description.


title: CAVEATS
content:
<b>Behavioral Difference from Git:</b> Unlike <i>git commit</i>, <i>jj-commit</i> does not create a new commit on top of the previous one if there are uncommitted changes. Instead, it <b>amends</b> the current working copy commit. To create a truly separate new commit, you would typically use <i>jj new</i> first. <br><br><b>Automatic Inclusion:</b> By default, <i>jj-commit</i> includes all modified and untracked files in the commit, similar to <i>git commit -a</i>. An explicit 'staging area' as seen in Git is not present in Jujutsu's default workflow.


title: WORKING COPY COMMIT CONCEPT
content:
In Jujutsu, your working directory is always associated with a specific 'working copy commit'. All your edits and uncommitted changes are conceptually applied on top of this commit. <i>jj-commit</i> directly targets and updates this specific commit, making the workflow feel more fluid and less reliant on managing an intermediate staging area.


title: IMPLICIT STAGING
content:
One of Jujutsu's distinct features is the absence of an explicit staging area (like Git's index). When you run <i>jj commit</i> (without <i>--interactive</i>), all changes in your working directory, including modifications to tracked files and new untracked files, are automatically considered for the commit. This design choice aims to simplify the most common commit workflows.


title: HISTORY
content:
<b>Jujutsu (jj)</b> is a relatively modern distributed version control system, open-sourced by <b>Google</b>. It was designed to offer a fresh perspective on version control, aiming to improve upon common pain points found in traditional systems like Git, especially concerning mutable history and large monorepo management. <i>jj-commit</i> is a core command that embodies Jujutsu's design philosophy, simplifying the commit workflow by integrating the 'staging' step and defaulting to amending the working copy commit, thereby streamlining common user interactions.


title: TLDR
content:
<b>Open editor to write the commit message and then create a new empty commit on top</b>`jj commit`<br><b>Commit with the given message</b>`jj commit [[-m|--message]] "[message]"`<br><b>Interactively choose which changes to include</b>`jj commit [[-i|--interactive]]`


title: PARAMETERS
content:
<b>--limit <i>&lt;COUNT&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Limit the number of commits displayed to <i>COUNT</i>.<br><br><b>--no-graph</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Suppress drawing the commit graph in the output.<br><br><b>--patch</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Show the full diff (patch) for each displayed commit.<br><br><b>--stat</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Show a summary of changes (files added, deleted, modified) for each commit.<br><br><b>--template <i>&lt;TEMPLATE&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Use a custom template string to format the output of each commit. This offers extensive customization.<br><br><b>--revisions <i>&lt;EXPRESSION&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Filter commits based on a revset expression. This allows powerful selection of specific commits or ranges.<br><br><b>--branches</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Show only commits that are local branches.<br><br><b>--remote-branches</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Show only commits that are remote branches.<br><br><b>--tags</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Show only commits that are tagged.<br><br><b>--glob <i>&lt;GLOB&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Filter commits by paths matching the given glob pattern.<br><br><b>--from-file <i>&lt;FILE&gt;</i></b><br>&nbsp;&nbsp;&nbsp;&nbsp;Read revisions to display from the specified file.<br><br><b>--reversed</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Display commits in reverse chronological order (oldest first).<br><br><b>--isolated</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Do not show changes from descendant commits, showing only the direct commit's changes.<br><br><b>--merge-labels</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Show merge labels on the graph edges to indicate merge directions.<br><br><b>--git</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Format the output similar to Git's default log output.<br><br>


title: DESCRIPTION
content:
The <b>jj-log</b> command is a fundamental tool within the <I>Jujutsu</I> (jj) version control system, analogous to Git's <b>git log</b>. It provides a visual representation of the repository's commit history, displaying commits, their relationships (parents and children), and associated changes.<br><br>Unlike traditional VCS tools that might linearize history, <b>jj-log</b> excels at visualizing Jujutsu's explicit Directed Acyclic Graph (DAG) of commits. This is particularly useful in Jujutsu's rebase-centric workflow and with its mutable history model, allowing users to understand how commits have evolved and been rearranged. It helps in tracing the lineage of changes, identifying specific points in history, and navigating the complex landscape of a <I>jj</I> repository efficiently.<br><br>Its strength lies in its ability to present a clear, interactive graph of commits and its powerful filtering and formatting capabilities, making it indispensable for any <I>Jujutsu</I> user.


title: CAVEATS
content:
Understanding Jujutsu's unique DAG structure and the <I>revset</I> language is key to effectively using <b>jj-log</b>'s advanced features, particularly with its mutable history and rebase-centric workflow.<br><br>The default graphical output can be dense for large histories, requiring familiarity with its symbols or custom templating for clarity.


title: POWERFUL TEMPLATE ENGINE
content:
One of <b>jj-log</b>'s most distinctive features is its highly customizable output via the <b>--template</b> option. Users can define precise formatting using a rich template language, including access to commit metadata (ID, author, date, description) and graph drawing elements. This enables unparalleled flexibility to tailor the history view to specific needs, from simple one-line summaries to detailed, multi-line commit blocks.


title: REVSET LANGUAGE FOR FILTERING
content:
The <b>--revisions</b> argument leverages Jujutsu's powerful "revset" language. This mini-language allows users to express complex queries for selecting sets of revisions, based on relationships (e.g., descendants, ancestors), branches, tags, or commit properties. This makes <b>jj-log</b> incredibly versatile for focused history exploration, debugging, or auditing specific parts of the commit graph.


title: HISTORY
content:
<b>jj-log</b> is an intrinsic part of the <I>Jujutsu</I> version control system, initially developed by Martin Pool. Its design is deeply intertwined with Jujutsu's core philosophy of mutable history and an explicit, visual commit graph. It has evolved alongside the <I>jj</I> command set to provide a comprehensive and intuitive way to explore the repository's state and changes, reflecting <I>Jujutsu's</I> distinct approach to branching, rebasing, and history management.


title: TLDR
content:
<b>Show revision history as a graph</b>`jj log`<br><b>Show only given revsets (e.g. B::D, A..D, B|C|D, etc.)</b>`jj log [[-r|--revisions]] [revsets]`<br><b>Show log with a particular template for each line (e.g. 5 characters of commit hash and author)</b>`jj log [[-T|--template]] 'commit_id.shortest(5) ++ " " ++ author'`


title: SYNOPSIS
content:
<b><i>mcli</i></b> <i>&lt;command&gt;</i> [<i>&lt;options&gt;</i>] [<i>&lt;arguments&gt;</i>]<br><br>The <i>mcli</i> command acts as a dispatcher for various subcommands, each with its own set of specific options and arguments.


title: PARAMETERS
content:
<b>query</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Used to retrieve detailed information about Mellanox devices, their drivers, capabilities, and current operational states. For example, <i>mcli query device</i> or <i>mcli query firmware</i>.<br><br><b>config</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Allows modification of various configuration settings for Mellanox network adapters and their associated drivers. Examples include setting port speeds, VFs, or other hardware parameters.<br><br><b>fw</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Dedicated to firmware management tasks, including querying the current firmware version of a device (<i>mcli fw query</i>) and performing firmware updates (<i>mcli fw update</i>).<br><br><b>diag</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Provides diagnostic capabilities to test the functionality and health of Mellanox devices and drivers, helping to identify and troubleshoot potential issues.<br><br><b>help</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Displays general help for the <i>mcli</i> utility or specific help for a subcommand when followed by the subcommand name (e.g., <i>mcli help query</i>).<br><br><b>version</b><br>&nbsp;&nbsp;&nbsp;&nbsp;Outputs the version information of the <i>mcli</i> command-line utility itself.<br><br>


title: DESCRIPTION
content:
The <i>mcli</i> command is the Mellanox Command Line Interface, a crucial utility for managing and configuring Mellanox (now NVIDIA) InfiniBand and Ethernet network adapters. It is typically distributed as part of the MLNX_OFED (Mellanox OpenFabrics Enterprise Distribution) or MLNX_EN (Mellanox Ethernet) driver packages. <i>mcli</i> provides a comprehensive set of tools for tasks such as querying device status and capabilities, modifying hardware and software configurations, managing firmware versions, and performing diagnostic checks. It allows administrators to fine-tune network performance, troubleshoot issues, and maintain the operational integrity of Mellanox-based networking infrastructure directly from the command line.


title: CAVEATS
content:
<i>mcli</i> is a proprietary utility specific to Mellanox (NVIDIA Networking) hardware and requires the installation of the MLNX_OFED or MLNX_EN driver packages. It is not a standard part of most Linux distributions and will not be available without the specific vendor driver installation. Functionality depends entirely on the presence and proper configuration of Mellanox network adapters.


title: DEPENDENCIES
content:
The <i>mcli</i> command relies on the presence of Mellanox/NVIDIA network adapters and the corresponding MLNX_OFED (Mellanox OpenFabrics Enterprise Distribution) or MLNX_EN (Mellanox Ethernet) driver packages. These drivers must be correctly installed and loaded for <i>mcli</i> to function.


title: HISTORY
content:
The <i>mcli</i> utility was developed by Mellanox Technologies as a core component of their network adapter software stack. Following NVIDIA's acquisition of Mellanox in 2020, <i>mcli</i> continues to be maintained and evolved as part of the NVIDIA Networking software offerings, supporting their ConnectX series of InfiniBand and Ethernet adapters.


title: SYNOPSIS
content:
<b>gdm</b> <br><i>Note: <i>gdm</i> is primarily a system daemon managed by init systems like <i>systemd</i>. Direct user invocation with command-line arguments is not typical for its operation.</i>


title: DESCRIPTION
content:
<i>gdm</i> stands for GNOME Display Manager. It is the official display manager for the GNOME desktop environment and is responsible for managing graphical login sessions on Linux and Unix-like operating systems. As a critical system service, <i>gdm</i> starts the X server or Wayland compositor, presents the graphical login screen, authenticates users, and launches their desktop sessions. It handles multiple user sessions, user switching, and remote display connections (via XDMCP). <i>gdm</i> ensures a secure and consistent graphical environment from boot-up to user session termination. Unlike many command-line utilities, <i>gdm</i> is typically run as a background daemon by the system's init process (e.g., <i>systemd</i>) rather than being invoked directly by users with command-line arguments. Its behavior is primarily configured via text files, typically located in <i>/etc/gdm3/</i>.


title: CAVEATS
content:
<ul><li><i>gdm</i> is a critical system service; improper configuration or manual manipulation can lead to inability to log in graphically.</li><li>It typically runs as <i>root</i> and manages sensitive operations like starting the display server and handling authentication.</li><li>Configuration is primarily done via text files (e.g., <i>/etc/gdm3/custom.conf</i>), not command-line arguments. Changes often require a service restart or system reboot to take effect.</li><li>Requires a correctly configured display server (Xorg or Wayland) and graphical drivers to function properly.</li></ul>


title: CONFIGURATION FILES
content:
The primary configuration for <i>gdm</i> is handled through files, typically found in <i>/etc/gdm3/</i>. The main configuration file is often <i>/etc/gdm3/custom.conf</i>, where administrators can customize settings such as default session, automatic login, theme, and Wayland/Xorg preference. Changes to these files usually require restarting the <i>gdm</i> service to take effect.


