zeus
4 years ago
297 changed files with 1 additions and 67851 deletions
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<meta name="description" content="Linux process management"> |
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<meta name="keywords" content="ps aux"> |
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<meta name="author" content="Apostolos rootApostolos@swarmlab.io"> |
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<title>Linux process management !</title> |
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</head> |
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<body class="article toc2 toc-right"> |
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<div id="header"> |
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<h1>Linux process management !</h1> |
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<div class="details"> |
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<span id="author" class="author">Apostolos rootApostolos@swarmlab.io</span><br> |
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</div> |
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<div id="toc" class="toc2"> |
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<div id="toctitle">Table of contents</div> |
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<ul class="sectlevel1"> |
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<li><a href="#_process">1. process</a></li> |
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<li><a href="#_linux_process_management">2. Linux process management</a></li> |
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</ul> |
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</div> |
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</div> |
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<div id="content"> |
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<div class="sect1"> |
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<h2 id="_process">1. process</h2> |
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<div class="sectionbody"> |
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<div class="paragraph"> |
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<p>An instance of a running program is called a process. |
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Every time you run a shell command, a program is run and a process is created for it.</p> |
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</div> |
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<div class="paragraph"> |
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<p>In any modern operating system there can be more than one instance of a program loaded in memory at the same time.</p> |
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</div> |
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</div> |
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</div> |
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<div class="sect1"> |
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<h2 id="_linux_process_management">2. Linux process management</h2> |
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<div class="sectionbody"> |
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<div class="paragraph"> |
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<p>Operating systems need some ways to create processes.</p> |
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</div> |
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<div class="ulist"> |
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<ul> |
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<li> |
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<p>In a very simple system designed for running only a single application (e.g., the controller in a microwave oven), it may be possible to have all the processes that will ever be needed be present when the system comes up.</p> |
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</li> |
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<li> |
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<p>In general-purpose systems, however, some way is needed to create and terminate processes as needed during operation.</p> |
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</li> |
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</ul> |
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</div> |
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<div class="admonitionblock note"> |
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<table> |
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<tr> |
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<td class="icon"> |
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<i class="fa icon-note" title="Note"></i> |
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</td> |
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<td class="content"> |
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<div class="paragraph"> |
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<p><strong>There are four principal events that cause a process to be created:</strong></p> |
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</div> |
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<div class="ulist"> |
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<ul> |
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<li> |
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<p>System initialization.</p> |
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</li> |
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<li> |
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<p>Execution of process creation system call by a running process.</p> |
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</li> |
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<li> |
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<p>A user request to create a new process.</p> |
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</li> |
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<li> |
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<p>Initiation of a batch job.</p> |
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</li> |
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</ul> |
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</div> |
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</td> |
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</tr> |
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</table> |
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</div> |
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<div class="paragraph"> |
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<p>Process creation in UNIX and Linux are done through <strong>fork()</strong> or <strong>clone()</strong> system calls.</p> |
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</div> |
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<div class="paragraph"> |
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<p>There are several steps involved in process creation.</p> |
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</div> |
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<div class="ulist"> |
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<ul> |
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<li> |
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<p>process scheduling,</p> |
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</li> |
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<li> |
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<p>interrupt handling,</p> |
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</li> |
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<li> |
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<p>signaling,</p> |
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</li> |
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<li> |
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<p>process prioritization,</p> |
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</li> |
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<li> |
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<p>process switching,</p> |
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</li> |
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<li> |
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<p>process state,</p> |
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</li> |
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<li> |
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<p>process memory</p> |
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</li> |
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</ul> |
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</div> |
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</div> |
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</div> |
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</div> |
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<script src="https://cdnjs.cloudflare.com/ajax/libs/highlight.js/9.18.3/highlight.min.js"></script> |
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<script> |
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<!DOCTYPE html> |
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<html lang="en"> |
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<head> |
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<meta charset="UTF-8"> |
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<meta http-equiv="X-UA-Compatible" content="IE=edge"> |
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<meta name="viewport" content="width=device-width, initial-scale=1.0"> |
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<meta name="generator" content="Asciidoctor 2.0.12"> |
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<meta name="description" content="Intro and Install"> |
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<meta name="keywords" content="Linux, apt"> |
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<meta name="author" content="Apostolos rootApostolos@swarmlab.io"> |
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<title>An Introduction to Linux !</title> |
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<link rel="stylesheet" href="http://cdnjs.cloudflare.com/ajax/libs/asciidoctor.js/1.5.9/css/asciidoctor.min.css"> |
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<link rel="stylesheet" href="http://cdnjs.cloudflare.com/ajax/libs/font-awesome/5.14.0/css/all.min.css"> |
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<link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/highlight.js/9.18.3/styles/github.min.css"> |
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</head> |
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<body class="article toc2 toc-right"> |
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<div id="header"> |
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<h1>An Introduction to Linux !</h1> |
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<div class="details"> |
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<span id="author" class="author">Apostolos rootApostolos@swarmlab.io</span><br> |
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</div> |
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<div id="toc" class="toc2"> |
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<div id="toctitle">Table of contents</div> |
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<ul class="sectlevel1"> |
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<li><a href="#_absolute_basics">1. Absolute basics</a> |
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<ul class="sectlevel2"> |
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<li><a href="#_key_combinations">1.1. Key combinations</a></li> |
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<li><a href="#_ls_l">1.2. ls -l</a> |
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<ul class="sectlevel3"> |
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<li><a href="#_file_types">1.2.1. File types</a></li> |
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<li><a href="#_access_rights">1.2.2. Access rights</a></li> |
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<li><a href="#_user_group_codes">1.2.3. User group codes</a></li> |
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<li><a href="#_exercises">1.2.4. Exercises</a></li> |
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</ul> |
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</li> |
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</ul> |
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</li> |
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</ul> |
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</div> |
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</div> |
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<div id="content"> |
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<div class="sect1"> |
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<h2 id="_absolute_basics">1. Absolute basics</h2> |
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<div class="sectionbody"> |
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<table class="tableblock frame-all grid-all stretch"> |
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<caption class="title">Table 1. Absolute basics</caption> |
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<colgroup> |
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<col style="width: 50%;"> |
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<col style="width: 50%;"> |
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</colgroup> |
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<thead> |
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<tr> |
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<th class="tableblock halign-left valign-top">Command</th> |
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<th class="tableblock halign-left valign-top">Meaning</th> |
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</tr> |
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</thead> |
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<tbody> |
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<tr> |
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<td class="tableblock halign-left valign-top"><p class="tableblock">ls</p></td> |
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<td class="tableblock halign-left valign-top"><p class="tableblock">Displays a list of files in the current working directory.</p></td> |
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</tr> |
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<tr> |
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<td class="tableblock halign-left valign-top"><p class="tableblock">cd directory</p></td> |
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<td class="tableblock halign-left valign-top"><p class="tableblock">change directories</p></td> |
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</tr> |
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<tr> |
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<td class="tableblock halign-left valign-top"><p class="tableblock">passwd</p></td> |
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<td class="tableblock halign-left valign-top"><p class="tableblock">change the password for the current user</p></td> |
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</tr> |
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<tr> |
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<td class="tableblock halign-left valign-top"><p class="tableblock">file filename</p></td> |
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<td class="tableblock halign-left valign-top"><p class="tableblock">display file type of file with name filename</p></td> |
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</tr> |
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<tr> |
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<td class="tableblock halign-left valign-top"><p class="tableblock">cat textfile</p></td> |
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<td class="tableblock halign-left valign-top"><p class="tableblock">throws content of textfile on the screen</p></td> |
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</tr> |
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<tr> |
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<td class="tableblock halign-left valign-top"><p class="tableblock">pwd</p></td> |
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<td class="tableblock halign-left valign-top"><p class="tableblock">display present working directory</p></td> |
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</tr> |
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<tr> |
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<td class="tableblock halign-left valign-top"><p class="tableblock">exit or logout</p></td> |
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<td class="tableblock halign-left valign-top"><p class="tableblock">leave this session</p></td> |
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</tr> |
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</tbody> |
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<tfoot> |
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<tr> |
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<td class="tableblock halign-left valign-top"><p class="tableblock">man command</p></td> |
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<td class="tableblock halign-left valign-top"><p class="tableblock">read man pages on command</p></td> |
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</tr> |
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</tfoot> |
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</table> |
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<div class="sect2"> |
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<h3 id="_key_combinations">1.1. Key combinations</h3> |
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<table class="tableblock frame-all grid-all stretch"> |
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<caption class="title">Table 2. Key combinations</caption> |
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<colgroup> |
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<col style="width: 50%;"> |
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<col style="width: 50%;"> |
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</colgroup> |
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<thead> |
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<tr> |
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<th class="tableblock halign-left valign-top">Key or key combination</th> |
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<th class="tableblock halign-left valign-top">Function</th> |
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</tr> |
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</thead> |
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<tbody> |
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<tr> |
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<td class="tableblock halign-left valign-top"><p class="tableblock">Ctrl+C</p></td> |
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<td class="tableblock halign-left valign-top"><p class="tableblock">End a running program and return the prompt</p></td> |
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</tr> |
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<tr> |
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<td class="tableblock halign-left valign-top"><p class="tableblock">Ctrl+Z</p></td> |
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<td class="tableblock halign-left valign-top"><p class="tableblock">Suspend a program</p></td> |
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</tr> |
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<tr> |
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<td class="tableblock halign-left valign-top"><p class="tableblock">ArrowUp and ArrowDown</p></td> |
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<td class="tableblock halign-left valign-top"><p class="tableblock">Browse history. Go to the line that you want to repeat, edit details if necessary, and press Enter to save time.</p></td> |
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</tr> |
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<tr> |
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<td class="tableblock halign-left valign-top"><p class="tableblock">Tab</p></td> |
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<td class="tableblock halign-left valign-top"><p class="tableblock">Command or filename completion; when multiple choices are possible, the system will either signal with an audio or visual bell, or, if too many choices are possible, ask you if you want to see them all.</p></td> |
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</tr> |
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<tr> |
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<td class="tableblock halign-left valign-top"><p class="tableblock">Tab Tab</p></td> |
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<td class="tableblock halign-left valign-top"><p class="tableblock">Shows file or command completion possibilities.</p></td> |
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</tr> |
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</tbody> |
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<tfoot> |
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<tr> |
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<td class="tableblock halign-left valign-top"><p class="tableblock">Shift+PageUp and Shift+PageDown</p></td> |
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<td class="tableblock halign-left valign-top"><p class="tableblock">Browse terminal buffer (to see text that has "scrolled off" the screen).</p></td> |
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</tr> |
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</tfoot> |
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</table> |
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</div> |
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<div class="sect2"> |
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<h3 id="_ls_l">1.2. ls -l</h3> |
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<div class="listingblock"> |
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<div class="content"> |
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<pre class="highlightjs highlight"><code class="language-bash hljs" data-lang="bash"># ls -al |
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drwxrwxr-x 4 zeus zeus 4096 Οκτ 23 21:55 . |
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drwxrwxr-x 9 zeus zeus 4096 Οκτ 15 14:28 .. |
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drwxrwxr-x 8 zeus zeus 4096 Οκτ 23 21:55 .git |
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drwxrwxr-x 4 zeus zeus 4096 Οκτ 14 20:24 install |
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crw------- 1 root root 5, 1 Οκτ 23 21:22 console |
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lrwxrwxrwx 1 root root 11 Οκτ 23 21:21 core -> /proc/kcore |
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drwxr-xr-x 4 root root 100 Οκτ 23 21:22 cpu |
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crw------- 1 root root 10, 59 Οκτ 23 21:21 cpu_dma_latency |
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crw------- 1 root root 10, 203 Οκτ 23 21:21 cuse |
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-rw-rw-r-- 1 zeus zeus 1517 Οκτ 23 21:55 INSTALL.md |
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-rw-rw-r-- 1 zeus zeus 33883 Οκτ 15 14:28 LICENSE |
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-rw-rw-r-- 1 zeus zeus 691 Οκτ 17 11:13 README.md</code></pre> |
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</div> |
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</div> |
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<div class="sect3"> |
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<h4 id="_file_types">1.2.1. File types</h4> |
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<div class="paragraph"> |
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<p>This table gives an overview of the characters determining the file type:</p> |
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</div> |
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<div class="admonitionblock note"> |
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<table> |
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<tr> |
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<td class="icon"> |
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<i class="fa icon-note" title="Note"></i> |
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</td> |
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<td class="content"> |
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<strong>d</strong>rwxrwxr-x 4 zeus zeus 4096 Οκτ 14 20:24 install |
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</td> |
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</tr> |
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</table> |
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</div> |
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<table class="tableblock frame-all grid-all stretch"> |
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<caption class="title">Table 3. File types in a long list</caption> |
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<colgroup> |
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<col style="width: 50%;"> |
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<col style="width: 50%;"> |
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</colgroup> |
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<thead> |
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<tr> |
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<th class="tableblock halign-left valign-top">Symbol</th> |
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<th class="tableblock halign-left valign-top">Meaning</th> |
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</tr> |
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</thead> |
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<tbody> |
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<tr> |
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<td class="tableblock halign-left valign-top"><p class="tableblock">-</p></td> |
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<td class="tableblock halign-left valign-top"><p class="tableblock">Regular file</p></td> |
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</tr> |
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<tr> |
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<td class="tableblock halign-left valign-top"><p class="tableblock">d</p></td> |
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<td class="tableblock halign-left valign-top"><p class="tableblock">Directory</p></td> |
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</tr> |
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<tr> |
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<td class="tableblock halign-left valign-top"><p class="tableblock">l</p></td> |
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<td class="tableblock halign-left valign-top"><p class="tableblock">Link</p></td> |
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</tr> |
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<tr> |
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<td class="tableblock halign-left valign-top"><p class="tableblock">c</p></td> |
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<td class="tableblock halign-left valign-top"><p class="tableblock">Special file</p></td> |
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</tr> |
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<tr> |
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<td class="tableblock halign-left valign-top"><p class="tableblock">s</p></td> |
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<td class="tableblock halign-left valign-top"><p class="tableblock">Socket</p></td> |
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</tr> |
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<tr> |
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<td class="tableblock halign-left valign-top"><p class="tableblock">p</p></td> |
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<td class="tableblock halign-left valign-top"><p class="tableblock">Named pipe</p></td> |
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</tr> |
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</tbody> |
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<tfoot> |
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<tr> |
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<td class="tableblock halign-left valign-top"><p class="tableblock">b</p></td> |
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<td class="tableblock halign-left valign-top"><p class="tableblock">Block device</p></td> |
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</tr> |
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</tfoot> |
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</table> |
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<div class="admonitionblock note"> |
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<table> |
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<tr> |
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<td class="icon"> |
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<i class="fa icon-note" title="Note"></i> |
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</td> |
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<td class="content"> |
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-<strong>rw-</strong>rw-r-- 1 zeus zeus 1517 Οκτ 23 21:55 INSTALL.md |
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</td> |
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</tr> |
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</table> |
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</div> |
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</div> |
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<div class="sect3"> |
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<h4 id="_access_rights">1.2.2. Access rights</h4> |
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<table class="tableblock frame-all grid-all stretch"> |
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<caption class="title">Table 4. Access rights</caption> |
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<colgroup> |
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<col style="width: 50%;"> |
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<col style="width: 50%;"> |
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</colgroup> |
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<thead> |
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<tr> |
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<th class="tableblock halign-left valign-top">Code</th> |
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<th class="tableblock halign-left valign-top">Meaning</th> |
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</tr> |
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</thead> |
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<tbody> |
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<tr> |
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<td class="tableblock halign-left valign-top"><p class="tableblock">0 or -</p></td> |
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<td class="tableblock halign-left valign-top"><p class="tableblock">The access right that is supposed to be on this place is not granted.</p></td> |
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</tr> |
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<tr> |
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<td class="tableblock halign-left valign-top"><p class="tableblock">4 or</p></td> |
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<td class="tableblock halign-left valign-top"><p class="tableblock">read access is granted to the user category defined in this place</p></td> |
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</tr> |
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<tr> |
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<td class="tableblock halign-left valign-top"><p class="tableblock">2 or</p></td> |
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<td class="tableblock halign-left valign-top"><p class="tableblock">write permission is granted to the user category defined in this place</p></td> |
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</tr> |
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</tbody> |
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<tfoot> |
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<tr> |
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<td class="tableblock halign-left valign-top"><p class="tableblock">1 or</p></td> |
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<td class="tableblock halign-left valign-top"><p class="tableblock">execute permission is granted to the user category defined in this place</p></td> |
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</tr> |
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</tfoot> |
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</table> |
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</div> |
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<div class="sect3"> |
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<h4 id="_user_group_codes">1.2.3. User group codes</h4> |
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<table class="tableblock frame-all grid-all stretch"> |
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<caption class="title">Table 5. User group codes</caption> |
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<colgroup> |
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<col style="width: 33.3333%;"> |
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<col style="width: 33.3333%;"> |
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<col style="width: 33.3334%;"> |
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</colgroup> |
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<thead> |
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<tr> |
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<th class="tableblock halign-left valign-top">Code</th> |
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<th class="tableblock halign-left valign-top">Meaning</th> |
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<th class="tableblock halign-left valign-top"></th> |
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</tr> |
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</thead> |
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<tbody> |
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<tr> |
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<td class="tableblock halign-left valign-top"><p class="tableblock">u</p></td> |
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<td class="tableblock halign-left valign-top"><p class="tableblock">user permissions</p></td> |
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<td class="tableblock halign-left valign-top"><p class="tableblock">-<strong>rw-</strong>rw-r--</p></td> |
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</tr> |
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<tr> |
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<td class="tableblock halign-left valign-top"><p class="tableblock">g</p></td> |
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<td class="tableblock halign-left valign-top"><p class="tableblock">group permissions</p></td> |
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<td class="tableblock halign-left valign-top"><p class="tableblock">-rw-<strong>rw-</strong>r--</p></td> |
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</tr> |
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</tbody> |
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<tfoot> |
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<tr> |
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<td class="tableblock halign-left valign-top"><p class="tableblock">o</p></td> |
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<td class="tableblock halign-left valign-top"><p class="tableblock">permissions for others</p></td> |
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<td class="tableblock halign-left valign-top"><p class="tableblock">-rw-rw-<strong>rw-</strong></p></td> |
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</tr> |
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</tfoot> |
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</table> |
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</div> |
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<div class="sect3"> |
|||
<h4 id="_exercises">1.2.4. Exercises</h4> |
|||
<div class="listingblock"> |
|||
<div class="content"> |
|||
<pre class="highlightjs highlight"><code class="language-bash hljs" data-lang="bash">touch example |
|||
chmod 400 example |
|||
ls -l example |
|||
chmod 500 example |
|||
ls -l example |
|||
chmod 600 example |
|||
ls -l example |
|||
chmod 644 example |
|||
ls -l example |
|||
chmod 660 example |
|||
ls -l example |
|||
chmod 700 example |
|||
ls -l example |
|||
chmod 755 example |
|||
ls -l example |
|||
chmod 775 example |
|||
ls -l example |
|||
ls -l example |
|||
chmod 777 example |
|||
ls -l example</code></pre> |
|||
</div> |
|||
</div> |
|||
<div class="paragraph"> |
|||
<p><br> |
|||
<br> |
|||
</p> |
|||
</div> |
|||
</div> |
|||
</div> |
|||
</div> |
|||
</div> |
|||
</div> |
|||
<script src="https://cdnjs.cloudflare.com/ajax/libs/highlight.js/9.18.3/highlight.min.js"></script> |
|||
<script> |
|||
if (!hljs.initHighlighting.called) { |
|||
hljs.initHighlighting.called = true |
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</html> |
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@ -1,328 +0,0 @@ |
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<!DOCTYPE html> |
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<html lang="en"> |
|||
<head> |
|||
<meta charset="UTF-8"> |
|||
<meta http-equiv="X-UA-Compatible" content="IE=edge"> |
|||
<meta name="viewport" content="width=device-width, initial-scale=1.0"> |
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<meta name="generator" content="Asciidoctor 2.0.12"> |
|||
<meta name="description" content="Intro and Install"> |
|||
<meta name="keywords" content="Linux, apt"> |
|||
<meta name="author" content="Apostolos rootApostolos@swarmlab.io"> |
|||
<title>An Introduction to Linux !</title> |
|||
<link rel="stylesheet" href="http://cdnjs.cloudflare.com/ajax/libs/asciidoctor.js/1.5.9/css/asciidoctor.min.css"> |
|||
<link rel="stylesheet" href="http://cdnjs.cloudflare.com/ajax/libs/font-awesome/5.14.0/css/all.min.css"> |
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|||
</head> |
|||
<body class="article toc2 toc-right"> |
|||
<div id="header"> |
|||
<h1>An Introduction to Linux !</h1> |
|||
<div class="details"> |
|||
<span id="author" class="author">Apostolos rootApostolos@swarmlab.io</span><br> |
|||
</div> |
|||
<div id="toc" class="toc2"> |
|||
<div id="toctitle">Table of contents</div> |
|||
<ul class="sectlevel1"> |
|||
<li><a href="#_absolute_basics">1. Absolute basics</a> |
|||
<ul class="sectlevel2"> |
|||
<li><a href="#_key_combinations">1.1. Key combinations</a></li> |
|||
<li><a href="#_ls_l">1.2. ls -l</a> |
|||
<ul class="sectlevel3"> |
|||
<li><a href="#_file_types">1.2.1. File types</a></li> |
|||
<li><a href="#_access_rights">1.2.2. Access rights</a></li> |
|||
<li><a href="#_user_group_codes">1.2.3. User group codes</a></li> |
|||
</ul> |
|||
</li> |
|||
</ul> |
|||
</li> |
|||
</ul> |
|||
</div> |
|||
</div> |
|||
<div id="content"> |
|||
<div id="preamble"> |
|||
<div class="sectionbody"> |
|||
<div class="paragraph"> |
|||
<p><br></p> |
|||
</div> |
|||
</div> |
|||
</div> |
|||
<div class="sect1"> |
|||
<h2 id="_absolute_basics">1. Absolute basics</h2> |
|||
<div class="sectionbody"> |
|||
<table class="tableblock frame-all grid-all stretch"> |
|||
<caption class="title">Table 1. Absolute basics</caption> |
|||
<colgroup> |
|||
<col style="width: 50%;"> |
|||
<col style="width: 50%;"> |
|||
</colgroup> |
|||
<thead> |
|||
<tr> |
|||
<th class="tableblock halign-left valign-top">Command</th> |
|||
<th class="tableblock halign-left valign-top">Meaning</th> |
|||
</tr> |
|||
</thead> |
|||
<tbody> |
|||
<tr> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">ls</p></td> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">Displays a list of files in the current working directory.</p></td> |
|||
</tr> |
|||
<tr> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">cd directory</p></td> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">change directories</p></td> |
|||
</tr> |
|||
<tr> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">passwd</p></td> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">change the password for the current user</p></td> |
|||
</tr> |
|||
<tr> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">file filename</p></td> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">display file type of file with name filename</p></td> |
|||
</tr> |
|||
<tr> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">cat textfile</p></td> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">throws content of textfile on the screen</p></td> |
|||
</tr> |
|||
<tr> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">pwd</p></td> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">display present working directory</p></td> |
|||
</tr> |
|||
<tr> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">exit or logout</p></td> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">leave this session</p></td> |
|||
</tr> |
|||
</tbody> |
|||
<tfoot> |
|||
<tr> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">man command</p></td> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">read man pages on command</p></td> |
|||
</tr> |
|||
</tfoot> |
|||
</table> |
|||
<div class="sect2"> |
|||
<h3 id="_key_combinations">1.1. Key combinations</h3> |
|||
<table class="tableblock frame-all grid-all stretch"> |
|||
<caption class="title">Table 2. Key combinations</caption> |
|||
<colgroup> |
|||
<col style="width: 50%;"> |
|||
<col style="width: 50%;"> |
|||
</colgroup> |
|||
<thead> |
|||
<tr> |
|||
<th class="tableblock halign-left valign-top">Key or key combination</th> |
|||
<th class="tableblock halign-left valign-top">Function</th> |
|||
</tr> |
|||
</thead> |
|||
<tbody> |
|||
<tr> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">Ctrl+C</p></td> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">End a running program and return the prompt</p></td> |
|||
</tr> |
|||
<tr> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">Ctrl+Z</p></td> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">Suspend a program</p></td> |
|||
</tr> |
|||
<tr> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">ArrowUp and ArrowDown</p></td> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">Browse history. Go to the line that you want to repeat, edit details if necessary, and press Enter to save time.</p></td> |
|||
</tr> |
|||
<tr> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">Tab</p></td> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">Command or filename completion; when multiple choices are possible, the system will either signal with an audio or visual bell, or, if too many choices are possible, ask you if you want to see them all.</p></td> |
|||
</tr> |
|||
<tr> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">Tab Tab</p></td> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">Shows file or command completion possibilities.</p></td> |
|||
</tr> |
|||
</tbody> |
|||
<tfoot> |
|||
<tr> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">Shift+PageUp and Shift+PageDown</p></td> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">Browse terminal buffer (to see text that has "scrolled off" the screen).</p></td> |
|||
</tr> |
|||
</tfoot> |
|||
</table> |
|||
</div> |
|||
<div class="sect2"> |
|||
<h3 id="_ls_l">1.2. ls -l</h3> |
|||
<div class="listingblock"> |
|||
<div class="content"> |
|||
<pre class="highlightjs highlight"><code class="language-bash hljs" data-lang="bash"># ls -al |
|||
drwxrwxr-x 4 zeus zeus 4096 Οκτ 23 21:55 . |
|||
drwxrwxr-x 9 zeus zeus 4096 Οκτ 15 14:28 .. |
|||
drwxrwxr-x 8 zeus zeus 4096 Οκτ 23 21:55 .git |
|||
drwxrwxr-x 4 zeus zeus 4096 Οκτ 14 20:24 install |
|||
crw------- 1 root root 5, 1 Οκτ 23 21:22 console |
|||
lrwxrwxrwx 1 root root 11 Οκτ 23 21:21 core -> /proc/kcore |
|||
drwxr-xr-x 4 root root 100 Οκτ 23 21:22 cpu |
|||
crw------- 1 root root 10, 59 Οκτ 23 21:21 cpu_dma_latency |
|||
crw------- 1 root root 10, 203 Οκτ 23 21:21 cuse |
|||
-rw-rw-r-- 1 zeus zeus 1517 Οκτ 23 21:55 INSTALL.md |
|||
-rw-rw-r-- 1 zeus zeus 33883 Οκτ 15 14:28 LICENSE |
|||
-rw-rw-r-- 1 zeus zeus 691 Οκτ 17 11:13 README.md</code></pre> |
|||
</div> |
|||
</div> |
|||
<div class="sect3"> |
|||
<h4 id="_file_types">1.2.1. File types</h4> |
|||
<div class="paragraph"> |
|||
<p>This table gives an overview of the characters determining the file type:</p> |
|||
</div> |
|||
<div class="admonitionblock note"> |
|||
<table> |
|||
<tr> |
|||
<td class="icon"> |
|||
<i class="fa icon-note" title="Note"></i> |
|||
</td> |
|||
<td class="content"> |
|||
<strong>d</strong>rwxrwxr-x 4 zeus zeus 4096 Οκτ 14 20:24 install |
|||
</td> |
|||
</tr> |
|||
</table> |
|||
</div> |
|||
<table class="tableblock frame-all grid-all stretch"> |
|||
<caption class="title">Table 3. File types in a long list</caption> |
|||
<colgroup> |
|||
<col style="width: 50%;"> |
|||
<col style="width: 50%;"> |
|||
</colgroup> |
|||
<thead> |
|||
<tr> |
|||
<th class="tableblock halign-left valign-top">Symbol</th> |
|||
<th class="tableblock halign-left valign-top">Meaning</th> |
|||
</tr> |
|||
</thead> |
|||
<tbody> |
|||
<tr> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">-</p></td> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">Regular file</p></td> |
|||
</tr> |
|||
<tr> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">d</p></td> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">Directory</p></td> |
|||
</tr> |
|||
<tr> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">l</p></td> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">Link</p></td> |
|||
</tr> |
|||
<tr> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">c</p></td> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">Special file</p></td> |
|||
</tr> |
|||
<tr> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">s</p></td> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">Socket</p></td> |
|||
</tr> |
|||
<tr> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">p</p></td> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">Named pipe</p></td> |
|||
</tr> |
|||
</tbody> |
|||
<tfoot> |
|||
<tr> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">b</p></td> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">Block device</p></td> |
|||
</tr> |
|||
</tfoot> |
|||
</table> |
|||
<div class="admonitionblock note"> |
|||
<table> |
|||
<tr> |
|||
<td class="icon"> |
|||
<i class="fa icon-note" title="Note"></i> |
|||
</td> |
|||
<td class="content"> |
|||
-<strong>rw-</strong>rw-r-- 1 zeus zeus 1517 Οκτ 23 21:55 INSTALL.md |
|||
</td> |
|||
</tr> |
|||
</table> |
|||
</div> |
|||
</div> |
|||
<div class="sect3"> |
|||
<h4 id="_access_rights">1.2.2. Access rights</h4> |
|||
<table class="tableblock frame-all grid-all stretch"> |
|||
<caption class="title">Table 4. Access rights</caption> |
|||
<colgroup> |
|||
<col style="width: 50%;"> |
|||
<col style="width: 50%;"> |
|||
</colgroup> |
|||
<thead> |
|||
<tr> |
|||
<th class="tableblock halign-left valign-top">Code</th> |
|||
<th class="tableblock halign-left valign-top">Meaning</th> |
|||
</tr> |
|||
</thead> |
|||
<tbody> |
|||
<tr> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">0 or -</p></td> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">The access right that is supposed to be on this place is not granted.</p></td> |
|||
</tr> |
|||
<tr> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">4 or</p></td> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">read access is granted to the user category defined in this place</p></td> |
|||
</tr> |
|||
<tr> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">2 or</p></td> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">write permission is granted to the user category defined in this place</p></td> |
|||
</tr> |
|||
</tbody> |
|||
<tfoot> |
|||
<tr> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">1 or</p></td> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">execute permission is granted to the user category defined in this place</p></td> |
|||
</tr> |
|||
</tfoot> |
|||
</table> |
|||
</div> |
|||
<div class="sect3"> |
|||
<h4 id="_user_group_codes">1.2.3. User group codes</h4> |
|||
<table class="tableblock frame-all grid-all stretch"> |
|||
<caption class="title">Table 5. User group codes</caption> |
|||
<colgroup> |
|||
<col style="width: 33.3333%;"> |
|||
<col style="width: 33.3333%;"> |
|||
<col style="width: 33.3334%;"> |
|||
</colgroup> |
|||
<thead> |
|||
<tr> |
|||
<th class="tableblock halign-left valign-top">Code</th> |
|||
<th class="tableblock halign-left valign-top">Meaning</th> |
|||
<th class="tableblock halign-left valign-top"></th> |
|||
</tr> |
|||
</thead> |
|||
<tbody> |
|||
<tr> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">u</p></td> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">user permissions</p></td> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">-<strong>rw-</strong>rw-r--</p></td> |
|||
</tr> |
|||
<tr> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">g</p></td> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">group permissions</p></td> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">-rw-<strong>rw-</strong>r--</p></td> |
|||
</tr> |
|||
</tbody> |
|||
<tfoot> |
|||
<tr> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">o</p></td> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">permissions for others</p></td> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">-rw-rw-<strong>rw-</strong></p></td> |
|||
</tr> |
|||
</tfoot> |
|||
</table> |
|||
<div class="paragraph"> |
|||
<p><br> |
|||
<br> |
|||
</p> |
|||
</div> |
|||
</div> |
|||
</div> |
|||
</div> |
|||
</div> |
|||
</div> |
|||
<script src="https://cdnjs.cloudflare.com/ajax/libs/highlight.js/9.18.3/highlight.min.js"></script> |
|||
<script> |
|||
if (!hljs.initHighlighting.called) { |
|||
hljs.initHighlighting.called = true |
|||
;[].slice.call(document.querySelectorAll('pre.highlight > code')).forEach(function (el) { hljs.highlightBlock(el) }) |
|||
} |
|||
</script> |
|||
</body> |
|||
</html> |
|||
@ -1,276 +0,0 @@ |
|||
<!DOCTYPE html> |
|||
<html lang="en"> |
|||
<head> |
|||
<meta charset="UTF-8"> |
|||
<meta http-equiv="X-UA-Compatible" content="IE=edge"> |
|||
<meta name="viewport" content="width=device-width, initial-scale=1.0"> |
|||
<meta name="generator" content="Asciidoctor 2.0.12"> |
|||
<meta name="description" content="Linux process management"> |
|||
<meta name="keywords" content="ps aux"> |
|||
<meta name="author" content="Apostolos rootApostolos@swarmlab.io"> |
|||
<title>Linux process management !</title> |
|||
<link rel="stylesheet" href="http://cdnjs.cloudflare.com/ajax/libs/asciidoctor.js/1.5.9/css/asciidoctor.min.css"> |
|||
<link rel="stylesheet" href="http://cdnjs.cloudflare.com/ajax/libs/font-awesome/5.14.0/css/all.min.css"> |
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<link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/highlight.js/9.18.3/styles/github.min.css"> |
|||
</head> |
|||
<body class="article toc2 toc-right"> |
|||
<div id="header"> |
|||
<h1>Linux process management !</h1> |
|||
<div class="details"> |
|||
<span id="author" class="author">Apostolos rootApostolos@swarmlab.io</span><br> |
|||
</div> |
|||
<div id="toc" class="toc2"> |
|||
<div id="toctitle">Table of contents</div> |
|||
<ul class="sectlevel1"> |
|||
<li><a href="#_process">1. process</a></li> |
|||
<li><a href="#_linux_process_management">2. Linux process management</a> |
|||
<ul class="sectlevel2"> |
|||
<li><a href="#_life_cycle_of_a_process">2.1. Life cycle of a process</a></li> |
|||
<li><a href="#_process_state">2.2. process state</a></li> |
|||
<li><a href="#_inter_process_communication">2.3. Inter-process communication</a> |
|||
<ul class="sectlevel3"> |
|||
<li><a href="#_communication_between_processes">2.3.1. communication between processes</a></li> |
|||
</ul> |
|||
</li> |
|||
</ul> |
|||
</li> |
|||
</ul> |
|||
</div> |
|||
</div> |
|||
<div id="content"> |
|||
<div class="sect1"> |
|||
<h2 id="_process">1. process</h2> |
|||
<div class="sectionbody"> |
|||
<div class="paragraph"> |
|||
<p>An instance of a running program is called a process. |
|||
Every time you run a shell command, a program is run and a process is created for it.</p> |
|||
</div> |
|||
<div class="paragraph"> |
|||
<p>In any modern operating system there can be more than one instance of a program loaded in memory at the same time.</p> |
|||
</div> |
|||
</div> |
|||
</div> |
|||
<div class="sect1"> |
|||
<h2 id="_linux_process_management">2. Linux process management</h2> |
|||
<div class="sectionbody"> |
|||
<div class="paragraph"> |
|||
<p>Operating systems need some ways to create processes.</p> |
|||
</div> |
|||
<div class="ulist"> |
|||
<ul> |
|||
<li> |
|||
<p>In a very simple system designed for running only a single application (e.g., the controller in a microwave oven), it may be possible to have all the processes that will ever be needed be present when the system comes up.</p> |
|||
</li> |
|||
<li> |
|||
<p>In general-purpose systems, however, some way is needed to create and terminate processes as needed during operation.</p> |
|||
</li> |
|||
</ul> |
|||
</div> |
|||
<div class="admonitionblock note"> |
|||
<table> |
|||
<tr> |
|||
<td class="icon"> |
|||
<i class="fa icon-note" title="Note"></i> |
|||
</td> |
|||
<td class="content"> |
|||
<div class="paragraph"> |
|||
<p><strong>There are four principal events that cause a process to be created:</strong></p> |
|||
</div> |
|||
<div class="ulist"> |
|||
<ul> |
|||
<li> |
|||
<p>System initialization.</p> |
|||
</li> |
|||
<li> |
|||
<p>Execution of process creation system call by a running process.</p> |
|||
</li> |
|||
<li> |
|||
<p>A user request to create a new process.</p> |
|||
</li> |
|||
<li> |
|||
<p>Initiation of a batch job.</p> |
|||
</li> |
|||
</ul> |
|||
</div> |
|||
</td> |
|||
</tr> |
|||
</table> |
|||
</div> |
|||
<div class="paragraph"> |
|||
<p>Process creation in UNIX and Linux are done through <strong>fork()</strong> or <strong>clone()</strong> system calls.</p> |
|||
</div> |
|||
<div class="paragraph"> |
|||
<p>There are several steps involved in process creation.</p> |
|||
</div> |
|||
<div class="ulist"> |
|||
<ul> |
|||
<li> |
|||
<p>process scheduling,</p> |
|||
</li> |
|||
<li> |
|||
<p>interrupt handling,</p> |
|||
</li> |
|||
<li> |
|||
<p>signaling,</p> |
|||
</li> |
|||
<li> |
|||
<p>process prioritization,</p> |
|||
</li> |
|||
<li> |
|||
<p>process switching,</p> |
|||
</li> |
|||
<li> |
|||
<p>process state,</p> |
|||
</li> |
|||
<li> |
|||
<p>process memory</p> |
|||
</li> |
|||
</ul> |
|||
</div> |
|||
<div class="sect2"> |
|||
<h3 id="_life_cycle_of_a_process">2.1. Life cycle of a process</h3> |
|||
<div class="admonitionblock note"> |
|||
<table> |
|||
<tr> |
|||
<td class="icon"> |
|||
<i class="fa icon-note" title="Note"></i> |
|||
</td> |
|||
<td class="content"> |
|||
<strong>1→</strong> creation <strong>2→</strong> execution <strong>3→</strong> termination <strong>4→</strong> removal |
|||
</td> |
|||
</tr> |
|||
</table> |
|||
</div> |
|||
</div> |
|||
<div class="sect2"> |
|||
<h3 id="_process_state">2.2. process state</h3> |
|||
<div class="paragraph"> |
|||
<p>An operating system kernel that allows multitasking needs processes to have certain states. Names for these states are not standardised, but they have similar functionality.</p> |
|||
</div> |
|||
<div class="openblock float-group"> |
|||
<div class="content"> |
|||
<div class="imageblock related thumb right"> |
|||
<div class="content"> |
|||
<img src="http://localhost:3080/images/Process_states.png" alt="350" width="350"> |
|||
</div> |
|||
</div> |
|||
<div class="ulist"> |
|||
<ul> |
|||
<li> |
|||
<p>the process is <strong>"created"</strong>.</p> |
|||
</li> |
|||
<li> |
|||
<p>After that the process scheduler assigns it the <strong>"waiting"</strong> state.</p> |
|||
</li> |
|||
<li> |
|||
<p>While the process is <strong>"waiting"</strong>, it waits for the scheduler to do a so-called context switch.</p> |
|||
</li> |
|||
<li> |
|||
<p>The context switch loads the process into the processor and changes the state to <strong>"running"</strong> while the previously <strong>"running"</strong> process is stored in a <strong>"waiting"</strong> state.</p> |
|||
</li> |
|||
<li> |
|||
<p>If a process in the <strong>"running"</strong> state needs to wait for a resource, it is assigned the <strong>"blocked"</strong> state.</p> |
|||
</li> |
|||
<li> |
|||
<p>The process state is changed back to <strong>"waiting"</strong> when the process no longer needs to wait (in a blocked state).</p> |
|||
</li> |
|||
<li> |
|||
<p>Once the process <strong>finishes execution</strong>, or is <strong>terminated</strong> by the operating system, it is no longer needed.</p> |
|||
</li> |
|||
<li> |
|||
<p>The process is <strong>removed instantly</strong> or is moved to the <strong>"terminated"</strong> state.</p> |
|||
</li> |
|||
<li> |
|||
<p>When removed, it just waits to be <strong>removed from main memory</strong>.</p> |
|||
</li> |
|||
</ul> |
|||
</div> |
|||
</div> |
|||
</div> |
|||
</div> |
|||
<div class="sect2"> |
|||
<h3 id="_inter_process_communication">2.3. Inter-process communication</h3> |
|||
<div class="paragraph"> |
|||
<p>When processes need to communicate with each other they must share parts of their address spaces or use other forms of inter-process communication (IPC).</p> |
|||
</div> |
|||
<div class="ulist"> |
|||
<ul> |
|||
<li> |
|||
<p>For instance in a shell pipeline, the output of the first process need to pass to the second one.</p> |
|||
</li> |
|||
<li> |
|||
<p>another example is a task that can be decomposed into cooperating but partially independent processes which can run at once</p> |
|||
<div class="ulist"> |
|||
<ul> |
|||
<li> |
|||
<p>(i.e., using concurrency, or true parallelism - the latter model is a particular case of concurrent execution and is feasible whenever enough CPU cores are available for all the processes that are ready to run).</p> |
|||
</li> |
|||
</ul> |
|||
</div> |
|||
</li> |
|||
</ul> |
|||
</div> |
|||
<div class="admonitionblock note"> |
|||
<table> |
|||
<tr> |
|||
<td class="icon"> |
|||
<i class="fa icon-note" title="Note"></i> |
|||
</td> |
|||
<td class="content"> |
|||
It is even possible for two or more processes to be running on different machines that may run different operating system (OS), therefore some mechanisms for communication and synchronization (called communications protocols for distributed computing) are needed (e.g., the <strong>Message Passing Interface, often simply called MPI</strong>). |
|||
</td> |
|||
</tr> |
|||
</table> |
|||
</div> |
|||
<div class="sect3"> |
|||
<h4 id="_communication_between_processes">2.3.1. communication between processes</h4> |
|||
<div class="paragraph"> |
|||
<p>Processes can communicate with each other through:</p> |
|||
</div> |
|||
<div class="ulist"> |
|||
<ul> |
|||
<li> |
|||
<p>Shared Memory</p> |
|||
</li> |
|||
<li> |
|||
<p>Message passing</p> |
|||
</li> |
|||
</ul> |
|||
</div> |
|||
<div class="openblock float-group"> |
|||
<div class="content"> |
|||
<div class="imageblock related thumb right"> |
|||
<div class="content"> |
|||
<img src="http://localhost:3080/images/1-76.png" alt="350" width="350"> |
|||
</div> |
|||
</div> |
|||
<div class="imageblock related thumb left"> |
|||
<div class="content"> |
|||
<img src="http://localhost:3080/images/2-50.png" alt="350" width="350"> |
|||
</div> |
|||
</div> |
|||
</div> |
|||
</div> |
|||
<div class="paragraph"> |
|||
<p><sup class="footnote">[<a id="_footnoteref_1" class="footnote" href="#_footnotedef_1" title="View footnote.">1</a>]</sup></p> |
|||
</div> |
|||
</div> |
|||
</div> |
|||
</div> |
|||
</div> |
|||
</div> |
|||
<div id="footnotes"> |
|||
<hr> |
|||
<div class="footnote" id="_footnotedef_1"> |
|||
<a href="#_footnoteref_1">1</a>. <a href="https://www.geeksforgeeks.org/inter-process-communication-ipc/" class="bare" target="_blank" rel="noopener">https://www.geeksforgeeks.org/inter-process-communication-ipc/</a> |
|||
</div> |
|||
</div> |
|||
<script src="https://cdnjs.cloudflare.com/ajax/libs/highlight.js/9.18.3/highlight.min.js"></script> |
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</body> |
|||
</html> |
|||
@ -1,349 +0,0 @@ |
|||
<!DOCTYPE html> |
|||
<html lang="en"> |
|||
<head> |
|||
<meta charset="UTF-8"> |
|||
<meta http-equiv="X-UA-Compatible" content="IE=edge"> |
|||
<meta name="viewport" content="width=device-width, initial-scale=1.0"> |
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<meta name="generator" content="Asciidoctor 2.0.12"> |
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<meta name="description" content="Intro and Install"> |
|||
<meta name="keywords" content="Linux, apt"> |
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<meta name="author" content="Apostolos rootApostolos@swarmlab.io"> |
|||
<title>An Introduction to Linux !</title> |
|||
<link rel="stylesheet" href="http://cdnjs.cloudflare.com/ajax/libs/asciidoctor.js/1.5.9/css/asciidoctor.min.css"> |
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<link rel="stylesheet" href="http://cdnjs.cloudflare.com/ajax/libs/font-awesome/5.14.0/css/all.min.css"> |
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<link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/highlight.js/9.18.3/styles/github.min.css"> |
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</head> |
|||
<body class="article toc2 toc-right"> |
|||
<div id="header"> |
|||
<h1>An Introduction to Linux !</h1> |
|||
<div class="details"> |
|||
<span id="author" class="author">Apostolos rootApostolos@swarmlab.io</span><br> |
|||
</div> |
|||
<div id="toc" class="toc2"> |
|||
<div id="toctitle">Table of contents</div> |
|||
<ul class="sectlevel1"> |
|||
<li><a href="#_absolute_basics">1. Absolute basics</a> |
|||
<ul class="sectlevel2"> |
|||
<li><a href="#_key_combinations">1.1. Key combinations</a></li> |
|||
<li><a href="#_ls_l">1.2. ls -l</a> |
|||
<ul class="sectlevel3"> |
|||
<li><a href="#_file_types">1.2.1. File types</a></li> |
|||
<li><a href="#_access_rights">1.2.2. Access rights</a></li> |
|||
<li><a href="#_user_group_codes">1.2.3. User group codes</a></li> |
|||
<li><a href="#_exercises">1.2.4. Exercises</a></li> |
|||
</ul> |
|||
</li> |
|||
</ul> |
|||
</li> |
|||
</ul> |
|||
</div> |
|||
</div> |
|||
<div id="content"> |
|||
<div class="sect1"> |
|||
<h2 id="_absolute_basics">1. Absolute basics</h2> |
|||
<div class="sectionbody"> |
|||
<table class="tableblock frame-all grid-all stretch"> |
|||
<caption class="title">Table 1. Absolute basics</caption> |
|||
<colgroup> |
|||
<col style="width: 50%;"> |
|||
<col style="width: 50%;"> |
|||
</colgroup> |
|||
<thead> |
|||
<tr> |
|||
<th class="tableblock halign-left valign-top">Command</th> |
|||
<th class="tableblock halign-left valign-top">Meaning</th> |
|||
</tr> |
|||
</thead> |
|||
<tbody> |
|||
<tr> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">ls</p></td> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">Displays a list of files in the current working directory.</p></td> |
|||
</tr> |
|||
<tr> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">cd directory</p></td> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">change directories</p></td> |
|||
</tr> |
|||
<tr> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">passwd</p></td> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">change the password for the current user</p></td> |
|||
</tr> |
|||
<tr> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">file filename</p></td> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">display file type of file with name filename</p></td> |
|||
</tr> |
|||
<tr> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">cat textfile</p></td> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">throws content of textfile on the screen</p></td> |
|||
</tr> |
|||
<tr> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">pwd</p></td> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">display present working directory</p></td> |
|||
</tr> |
|||
<tr> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">exit or logout</p></td> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">leave this session</p></td> |
|||
</tr> |
|||
</tbody> |
|||
<tfoot> |
|||
<tr> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">man command</p></td> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">read man pages on command</p></td> |
|||
</tr> |
|||
</tfoot> |
|||
</table> |
|||
<div class="sect2"> |
|||
<h3 id="_key_combinations">1.1. Key combinations</h3> |
|||
<table class="tableblock frame-all grid-all stretch"> |
|||
<caption class="title">Table 2. Key combinations</caption> |
|||
<colgroup> |
|||
<col style="width: 50%;"> |
|||
<col style="width: 50%;"> |
|||
</colgroup> |
|||
<thead> |
|||
<tr> |
|||
<th class="tableblock halign-left valign-top">Key or key combination</th> |
|||
<th class="tableblock halign-left valign-top">Function</th> |
|||
</tr> |
|||
</thead> |
|||
<tbody> |
|||
<tr> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">Ctrl+C</p></td> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">End a running program and return the prompt</p></td> |
|||
</tr> |
|||
<tr> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">Ctrl+Z</p></td> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">Suspend a program</p></td> |
|||
</tr> |
|||
<tr> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">ArrowUp and ArrowDown</p></td> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">Browse history. Go to the line that you want to repeat, edit details if necessary, and press Enter to save time.</p></td> |
|||
</tr> |
|||
<tr> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">Tab</p></td> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">Command or filename completion; when multiple choices are possible, the system will either signal with an audio or visual bell, or, if too many choices are possible, ask you if you want to see them all.</p></td> |
|||
</tr> |
|||
<tr> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">Tab Tab</p></td> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">Shows file or command completion possibilities.</p></td> |
|||
</tr> |
|||
</tbody> |
|||
<tfoot> |
|||
<tr> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">Shift+PageUp and Shift+PageDown</p></td> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">Browse terminal buffer (to see text that has "scrolled off" the screen).</p></td> |
|||
</tr> |
|||
</tfoot> |
|||
</table> |
|||
</div> |
|||
<div class="sect2"> |
|||
<h3 id="_ls_l">1.2. ls -l</h3> |
|||
<div class="listingblock"> |
|||
<div class="content"> |
|||
<pre class="highlightjs highlight"><code class="language-bash hljs" data-lang="bash"># ls -al |
|||
drwxrwxr-x 4 zeus zeus 4096 Οκτ 23 21:55 . |
|||
drwxrwxr-x 9 zeus zeus 4096 Οκτ 15 14:28 .. |
|||
drwxrwxr-x 8 zeus zeus 4096 Οκτ 23 21:55 .git |
|||
drwxrwxr-x 4 zeus zeus 4096 Οκτ 14 20:24 install |
|||
crw------- 1 root root 5, 1 Οκτ 23 21:22 console |
|||
lrwxrwxrwx 1 root root 11 Οκτ 23 21:21 core -> /proc/kcore |
|||
drwxr-xr-x 4 root root 100 Οκτ 23 21:22 cpu |
|||
crw------- 1 root root 10, 59 Οκτ 23 21:21 cpu_dma_latency |
|||
crw------- 1 root root 10, 203 Οκτ 23 21:21 cuse |
|||
-rw-rw-r-- 1 zeus zeus 1517 Οκτ 23 21:55 INSTALL.md |
|||
-rw-rw-r-- 1 zeus zeus 33883 Οκτ 15 14:28 LICENSE |
|||
-rw-rw-r-- 1 zeus zeus 691 Οκτ 17 11:13 README.md</code></pre> |
|||
</div> |
|||
</div> |
|||
<div class="sect3"> |
|||
<h4 id="_file_types">1.2.1. File types</h4> |
|||
<div class="paragraph"> |
|||
<p>This table gives an overview of the characters determining the file type:</p> |
|||
</div> |
|||
<div class="admonitionblock note"> |
|||
<table> |
|||
<tr> |
|||
<td class="icon"> |
|||
<i class="fa icon-note" title="Note"></i> |
|||
</td> |
|||
<td class="content"> |
|||
<strong>d</strong>rwxrwxr-x 4 zeus zeus 4096 Οκτ 14 20:24 install |
|||
</td> |
|||
</tr> |
|||
</table> |
|||
</div> |
|||
<table class="tableblock frame-all grid-all stretch"> |
|||
<caption class="title">Table 3. File types in a long list</caption> |
|||
<colgroup> |
|||
<col style="width: 50%;"> |
|||
<col style="width: 50%;"> |
|||
</colgroup> |
|||
<thead> |
|||
<tr> |
|||
<th class="tableblock halign-left valign-top">Symbol</th> |
|||
<th class="tableblock halign-left valign-top">Meaning</th> |
|||
</tr> |
|||
</thead> |
|||
<tbody> |
|||
<tr> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">-</p></td> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">Regular file</p></td> |
|||
</tr> |
|||
<tr> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">d</p></td> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">Directory</p></td> |
|||
</tr> |
|||
<tr> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">l</p></td> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">Link</p></td> |
|||
</tr> |
|||
<tr> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">c</p></td> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">Special file</p></td> |
|||
</tr> |
|||
<tr> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">s</p></td> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">Socket</p></td> |
|||
</tr> |
|||
<tr> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">p</p></td> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">Named pipe</p></td> |
|||
</tr> |
|||
</tbody> |
|||
<tfoot> |
|||
<tr> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">b</p></td> |
|||
<td class="tableblock halign-left valign-top"><p class="tableblock">Block device</p></td> |
|||
</tr> |
|||
</tfoot> |
|||
</table> |
|||
<div class="admonitionblock note"> |
|||
<table> |
|||
<tr> |
|||
<td class="icon"> |
|||
<i class="fa icon-note" title="Note"></i> |
|||
</td> |
|||
<td class="content"> |
|||
-<strong>rw-</strong>rw-r-- 1 zeus zeus 1517 Οκτ 23 21:55 INSTALL.md |
|||
</td> |
|||
</tr> |
|||
</table> |
|||
</div> |
|||
</div> |
|||
<div class="sect3"> |
|||
<h4 id="_access_rights" | |||