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| author | johannst <johannst@users.noreply.github.com> | 2024-05-01 17:39:45 +0000 |
|---|---|---|
| committer | johannst <johannst@users.noreply.github.com> | 2024-05-01 17:39:45 +0000 |
| commit | 21a13652df728c9571f899caf4949d5d46f49db7 (patch) | |
| tree | dcd723453f6405c53a162da4c95896f5768f13d2 /tools/bash.html | |
| parent | 269caa8ae18eb33e1286e4c21d434ea07228a619 (diff) | |
| download | notes-21a13652df728c9571f899caf4949d5d46f49db7.tar.gz notes-21a13652df728c9571f899caf4949d5d46f49db7.zip | |
deploy: 7ca41565c4e70b212cb88a4d18c18fa35768df6d
Diffstat (limited to 'tools/bash.html')
| -rw-r--r-- | tools/bash.html | 457 |
1 files changed, 0 insertions, 457 deletions
diff --git a/tools/bash.html b/tools/bash.html deleted file mode 100644 index c990d81..0000000 --- a/tools/bash.html +++ /dev/null @@ -1,457 +0,0 @@ -<!DOCTYPE HTML> -<html lang="en" class="light" dir="ltr"> - <head> - <!-- Book generated using mdBook --> - <meta charset="UTF-8"> - <title>bash - Notes</title> - - - <!-- Custom HTML head --> - - <meta name="description" content=""> - <meta name="viewport" content="width=device-width, initial-scale=1"> - <meta name="theme-color" content="#ffffff"> - - <link rel="icon" href="../favicon.svg"> - <link rel="shortcut icon" href="../favicon.png"> - <link rel="stylesheet" href="../css/variables.css"> - <link rel="stylesheet" href="../css/general.css"> - <link rel="stylesheet" href="../css/chrome.css"> - <link rel="stylesheet" href="../css/print.css" media="print"> - - <!-- Fonts --> - <link rel="stylesheet" href="../FontAwesome/css/font-awesome.css"> - <link rel="stylesheet" href="../fonts/fonts.css"> - - <!-- Highlight.js Stylesheets --> - <link rel="stylesheet" href="../highlight.css"> - <link rel="stylesheet" href="../tomorrow-night.css"> - <link rel="stylesheet" href="../ayu-highlight.css"> - - <!-- Custom theme stylesheets --> - - </head> - <body class="sidebar-visible no-js"> - <div id="body-container"> - <!-- Provide site root to javascript --> - <script> - var path_to_root = "../"; - var default_theme = window.matchMedia("(prefers-color-scheme: dark)").matches ? "navy" : "light"; - </script> - - <!-- Work around some values being stored in localStorage wrapped in quotes --> - <script> - try { - var theme = localStorage.getItem('mdbook-theme'); - var sidebar = localStorage.getItem('mdbook-sidebar'); - - if (theme.startsWith('"') && theme.endsWith('"')) { - localStorage.setItem('mdbook-theme', theme.slice(1, theme.length - 1)); - } - - if (sidebar.startsWith('"') && sidebar.endsWith('"')) { - localStorage.setItem('mdbook-sidebar', sidebar.slice(1, sidebar.length - 1)); - } - } catch (e) { } - </script> - - <!-- Set the theme before any content is loaded, prevents flash --> - <script> - var theme; - try { theme = localStorage.getItem('mdbook-theme'); } catch(e) { } - if (theme === null || theme === undefined) { theme = default_theme; } - var html = document.querySelector('html'); - html.classList.remove('light') - html.classList.add(theme); - var body = document.querySelector('body'); - body.classList.remove('no-js') - body.classList.add('js'); - </script> - - <input type="checkbox" id="sidebar-toggle-anchor" class="hidden"> - - <!-- Hide / unhide sidebar before it is displayed --> - <script> - var body = document.querySelector('body'); - var sidebar = null; - var sidebar_toggle = document.getElementById("sidebar-toggle-anchor"); - if (document.body.clientWidth >= 1080) { - try { sidebar = localStorage.getItem('mdbook-sidebar'); } catch(e) { } - sidebar = sidebar || 'visible'; - } else { - sidebar = 'hidden'; - } - sidebar_toggle.checked = sidebar === 'visible'; - body.classList.remove('sidebar-visible'); - body.classList.add("sidebar-" + sidebar); - </script> - - <nav id="sidebar" class="sidebar" aria-label="Table of contents"> - <div class="sidebar-scrollbox"> - <ol class="chapter"><li class="chapter-item expanded affix "><a href="../intro.html">Introduction</a></li><li class="chapter-item expanded "><a href="../tools/index.html"><strong aria-hidden="true">1.</strong> Tools</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="../tools/zsh.html"><strong aria-hidden="true">1.1.</strong> zsh</a></li><li class="chapter-item expanded "><a href="../tools/bash.html" class="active"><strong aria-hidden="true">1.2.</strong> bash</a></li><li class="chapter-item expanded "><a href="../tools/fish.html"><strong aria-hidden="true">1.3.</strong> fish</a></li><li class="chapter-item expanded "><a href="../tools/tmux.html"><strong aria-hidden="true">1.4.</strong> tmux</a></li><li class="chapter-item expanded "><a href="../tools/git.html"><strong aria-hidden="true">1.5.</strong> git</a></li><li class="chapter-item expanded "><a href="../tools/awk.html"><strong aria-hidden="true">1.6.</strong> awk</a></li><li class="chapter-item expanded "><a href="../tools/emacs.html"><strong aria-hidden="true">1.7.</strong> emacs</a></li><li class="chapter-item expanded "><a href="../tools/gpg.html"><strong aria-hidden="true">1.8.</strong> gpg</a></li><li class="chapter-item expanded "><a href="../tools/gdb.html"><strong aria-hidden="true">1.9.</strong> gdb</a></li><li class="chapter-item expanded "><a href="../tools/gdbserver.html"><strong aria-hidden="true">1.10.</strong> gdbserver</a></li><li class="chapter-item expanded "><a href="../tools/radare2.html"><strong aria-hidden="true">1.11.</strong> radare2</a></li><li class="chapter-item expanded "><a href="../tools/qemu.html"><strong aria-hidden="true">1.12.</strong> qemu</a></li><li class="chapter-item expanded "><a href="../tools/pacman.html"><strong aria-hidden="true">1.13.</strong> pacman</a></li><li class="chapter-item expanded "><a href="../tools/dot.html"><strong aria-hidden="true">1.14.</strong> dot</a></li><li class="chapter-item expanded "><a href="../tools/ffmpeg.html"><strong aria-hidden="true">1.15.</strong> ffmpeg</a></li><li class="chapter-item expanded "><a href="../tools/column.html"><strong aria-hidden="true">1.16.</strong> column</a></li><li class="chapter-item expanded "><a href="../tools/sort.html"><strong aria-hidden="true">1.17.</strong> sort</a></li><li class="chapter-item expanded "><a href="../tools/sed.html"><strong aria-hidden="true">1.18.</strong> sed</a></li><li class="chapter-item expanded "><a href="../tools/gnuplot.html"><strong aria-hidden="true">1.19.</strong> gnuplot</a></li></ol></li><li class="chapter-item expanded "><a href="../monitor/index.html"><strong aria-hidden="true">2.</strong> Resource analysis & monitor</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="../monitor/lsof.html"><strong aria-hidden="true">2.1.</strong> lsof</a></li><li class="chapter-item expanded "><a href="../monitor/ss.html"><strong aria-hidden="true">2.2.</strong> ss</a></li><li class="chapter-item expanded "><a href="../monitor/pidstat.html"><strong aria-hidden="true">2.3.</strong> pidstat</a></li><li class="chapter-item expanded "><a href="../monitor/pgrep.html"><strong aria-hidden="true">2.4.</strong> pgrep</a></li><li class="chapter-item expanded "><a href="../monitor/ps.html"><strong aria-hidden="true">2.5.</strong> ps</a></li><li class="chapter-item expanded "><a href="../monitor/pmap.html"><strong aria-hidden="true">2.6.</strong> pmap</a></li><li class="chapter-item expanded "><a href="../monitor/pstack.html"><strong aria-hidden="true">2.7.</strong> pstack</a></li></ol></li><li class="chapter-item expanded "><a href="../trace_profile/index.html"><strong aria-hidden="true">3.</strong> Trace and Profile</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="../trace_profile/time.html"><strong aria-hidden="true">3.1.</strong> time</a></li><li class="chapter-item expanded "><a href="../trace_profile/strace.html"><strong aria-hidden="true">3.2.</strong> strace</a></li><li class="chapter-item expanded "><a href="../trace_profile/ltrace.html"><strong aria-hidden="true">3.3.</strong> ltrace</a></li><li class="chapter-item expanded "><a href="../trace_profile/perf.html"><strong aria-hidden="true">3.4.</strong> perf</a></li><li class="chapter-item expanded "><a href="../trace_profile/oprofile.html"><strong aria-hidden="true">3.5.</strong> OProfile</a></li><li class="chapter-item expanded "><a href="../trace_profile/callgrind.html"><strong aria-hidden="true">3.6.</strong> callgrind</a></li></ol></li><li class="chapter-item expanded "><a href="../binary/index.html"><strong aria-hidden="true">4.</strong> Binary</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="../binary/od.html"><strong aria-hidden="true">4.1.</strong> od</a></li><li class="chapter-item expanded "><a href="../binary/xxd.html"><strong aria-hidden="true">4.2.</strong> xxd</a></li><li class="chapter-item expanded "><a href="../binary/readelf.html"><strong aria-hidden="true">4.3.</strong> readelf</a></li><li class="chapter-item expanded "><a href="../binary/objdump.html"><strong aria-hidden="true">4.4.</strong> objdump</a></li><li class="chapter-item expanded "><a href="../binary/nm.html"><strong aria-hidden="true">4.5.</strong> nm</a></li></ol></li><li class="chapter-item expanded "><a href="../development/index.html"><strong aria-hidden="true">5.</strong> Development</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="../development/c++filt.html"><strong aria-hidden="true">5.1.</strong> c++filt</a></li><li class="chapter-item expanded "><a href="../development/c++.html"><strong aria-hidden="true">5.2.</strong> c++</a></li><li class="chapter-item expanded "><a href="../development/glibc.html"><strong aria-hidden="true">5.3.</strong> glibc</a></li><li class="chapter-item expanded "><a href="../development/gcc.html"><strong aria-hidden="true">5.4.</strong> gcc</a></li><li class="chapter-item expanded "><a href="../development/cmake.html"><strong aria-hidden="true">5.5.</strong> cmake</a></li><li class="chapter-item expanded "><a href="../development/make.html"><strong aria-hidden="true">5.6.</strong> make</a></li><li class="chapter-item expanded "><a href="../development/ld.so.html"><strong aria-hidden="true">5.7.</strong> ld.so</a></li><li class="chapter-item expanded "><a href="../development/symbolver.html"><strong aria-hidden="true">5.8.</strong> symbol versioning</a></li><li class="chapter-item expanded "><a href="../development/python.html"><strong aria-hidden="true">5.9.</strong> python</a></li><li class="chapter-item expanded "><a href="../development/gcov.html"><strong aria-hidden="true">5.10.</strong> gcov</a></li><li class="chapter-item expanded "><a href="../development/pgo.html"><strong aria-hidden="true">5.11.</strong> pgo</a></li></ol></li><li class="chapter-item expanded "><a href="../linux/index.html"><strong aria-hidden="true">6.</strong> Linux</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="../linux/systemd.html"><strong aria-hidden="true">6.1.</strong> systemd</a></li><li class="chapter-item expanded "><a href="../linux/coredump.html"><strong aria-hidden="true">6.2.</strong> coredump</a></li><li class="chapter-item expanded "><a href="../linux/ptrace_scope.html"><strong aria-hidden="true">6.3.</strong> ptrace_scope</a></li><li class="chapter-item expanded "><a href="../linux/cryptsetup.html"><strong aria-hidden="true">6.4.</strong> cryptsetup</a></li><li class="chapter-item expanded "><a href="../linux/swap.html"><strong aria-hidden="true">6.5.</strong> swap</a></li><li class="chapter-item expanded "><a href="../linux/input.html"><strong aria-hidden="true">6.6.</strong> input</a></li><li class="chapter-item expanded "><a href="../linux/acl.html"><strong aria-hidden="true">6.7.</strong> acl</a></li><li class="chapter-item expanded "><a href="../linux/zfs.html"><strong aria-hidden="true">6.8.</strong> zfs</a></li></ol></li><li class="chapter-item expanded "><a href="../network/index.html"><strong aria-hidden="true">7.</strong> Network</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="../network/tcpdump.html"><strong aria-hidden="true">7.1.</strong> tcpdump</a></li><li class="chapter-item expanded "><a href="../network/tshark.html"><strong aria-hidden="true">7.2.</strong> tshark</a></li><li class="chapter-item expanded "><a href="../network/firewall-cmd.html"><strong aria-hidden="true">7.3.</strong> firewall-cmd</a></li><li class="chapter-item expanded "><a href="../network/nftables.html"><strong aria-hidden="true">7.4.</strong> nftables</a></li></ol></li><li class="chapter-item expanded "><a href="../web/index.html"><strong aria-hidden="true">8.</strong> Web</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="../web/html.html"><strong aria-hidden="true">8.1.</strong> html</a></li><li class="chapter-item expanded "><a href="../web/css.html"><strong aria-hidden="true">8.2.</strong> css</a></li><li class="chapter-item expanded "><a href="../web/chartjs.html"><strong aria-hidden="true">8.3.</strong> chartjs</a></li></ol></li><li class="chapter-item expanded "><a href="../arch/index.html"><strong aria-hidden="true">9.</strong> Arch</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="../arch/x86_64.html"><strong aria-hidden="true">9.1.</strong> x86_64</a></li><li class="chapter-item expanded "><a href="../arch/arm64.html"><strong aria-hidden="true">9.2.</strong> arm64</a></li><li class="chapter-item expanded "><a href="../arch/armv7.html"><strong aria-hidden="true">9.3.</strong> armv7</a></li><li class="chapter-item expanded "><a href="../arch/riscv.html"><strong aria-hidden="true">9.4.</strong> riscv</a></li></ol></li></ol> - </div> - <div id="sidebar-resize-handle" class="sidebar-resize-handle"> - <div class="sidebar-resize-indicator"></div> - </div> - </nav> - - <!-- Track and set sidebar scroll position --> - <script> - var sidebarScrollbox = document.querySelector('#sidebar .sidebar-scrollbox'); - sidebarScrollbox.addEventListener('click', function(e) { - if (e.target.tagName === 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(Shortkey: s)" aria-label="Toggle Searchbar" aria-expanded="false" aria-keyshortcuts="S" aria-controls="searchbar"> - <i class="fa fa-search"></i> - </button> - </div> - - <h1 class="menu-title">Notes</h1> - - <div class="right-buttons"> - <a href="../print.html" title="Print this book" aria-label="Print this book"> - <i id="print-button" class="fa fa-print"></i> - </a> - <a href="https://github.com/johannst/notes" title="Git repository" aria-label="Git repository"> - <i id="git-repository-button" class="fa fa-github"></i> - </a> - - </div> - </div> - - <div id="search-wrapper" class="hidden"> - <form id="searchbar-outer" class="searchbar-outer"> - <input type="search" id="searchbar" name="searchbar" placeholder="Search this book ..." aria-controls="searchresults-outer" aria-describedby="searchresults-header"> - </form> - <div id="searchresults-outer" class="searchresults-outer hidden"> - <div id="searchresults-header" class="searchresults-header"></div> - <ul id="searchresults"> - </ul> - </div> - </div> - - <!-- Apply ARIA attributes after the sidebar and the sidebar toggle button are added to the DOM --> - <script> - document.getElementById('sidebar-toggle').setAttribute('aria-expanded', sidebar === 'visible'); - document.getElementById('sidebar').setAttribute('aria-hidden', sidebar !== 'visible'); - Array.from(document.querySelectorAll('#sidebar a')).forEach(function(link) { - link.setAttribute('tabIndex', sidebar === 'visible' ? 0 : -1); - }); - </script> - - <div id="content" class="content"> - <main> - <h1 id="bash1"><a class="header" href="#bash1">bash(1)</a></h1> -<h2 id="expansion"><a class="header" href="#expansion">Expansion</a></h2> -<h3 id="generator"><a class="header" href="#generator">Generator</a></h3> -<pre><code class="language-bash"># generate sequence from n to m -{n..m} -# generate sequence from n to m step by s -{n..m..s} - -# expand cartesian product -{a,b}{c,d} -</code></pre> -<h3 id="parameter"><a class="header" href="#parameter">Parameter</a></h3> -<pre><code class="language-bash"># default value -bar=${foo:-some_val} # if $foo set, then bar=$foo else bar=some_val - -# alternate value -bar=${foo:+bla $foo} # if $foo set, then bar="bla $foo" else bar="" - -# check param set -bar=${foo:?msg} # if $foo set, then bar=$foo else exit and print msg - -# indirect -FOO=foo -BAR=FOO -bar=${!BAR} # deref value of BAR -> bar=$FOO - -# prefix -${foo#prefix} # remove prefix when expanding $foo -# suffix -${foo%suffix} # remove suffix when expanding $foo - -# substitute -${foo/pattern/string} # replace pattern with string when expanding foo -# pattern starts with -# '/' replace all occurences of pattern -# '#' pattern match at beginning -# '%' pattern match at end - -# set programmatically with priintf builtin -printf -v "VAR1" "abc" -NAME=VAR2 -printf -v "$NAME" "%s" "def" -</code></pre> -<blockquote> -<p>Note: <code>prefix</code>/<code>suffix</code>/<code>pattern</code> are expanded as <a href="#pathname">pathnames</a>.</p> -</blockquote> -<h3 id="pathname"><a class="header" href="#pathname">Pathname</a></h3> -<pre><code class="language-bash">* match any string -? match any single char -\\ match backslash -[abc] match any char of 'a' 'b' 'c' -[a-z] match any char between 'a' - 'z' -[^ab] negate, match all not 'a' 'b' -[:class:] match any char in class, available: - alnum,alpha,ascii,blank,cntrl,digit,graph,lower, - print,punct,space,upper,word,xdigit -</code></pre> -<p>With <code>extglob</code> shell option enabled it is possible to have more powerful -patterns. In the following <code>pattern-list</code> is one ore more patterns separated -by <code>|</code> char.</p> -<pre><code class="language-bash">?(pattern-list) matches zero or one occurrence of the given patterns -*(pattern-list) matches zero or more occurrences of the given patterns -+(pattern-list) matches one or more occurrences of the given patterns -@(pattern-list) matches one of the given patterns -!(pattern-list) matches anything except one of the given patterns -</code></pre> -<blockquote> -<p>Note: <code>shopt -s extglob</code>/<code>shopt -u extglob</code> to enable/disable <code>extglob</code> -option.</p> -</blockquote> -<h2 id="io-redirection"><a class="header" href="#io-redirection">I/O redirection</a></h2> -<blockquote> -<p>Note: The trick with bash I/O redirection is to interpret from left-to-right.</p> -</blockquote> -<pre><code class="language-bash"># stdout & stderr to file -command >file 2>&1 -# equivalent -command &>file - -# stderr to stdout & stdout to file -command 2>&1 >file -</code></pre> -<blockquote> -<p>The article <a href="https://catonmat.net/bash-one-liners-explained-part-three">Bash One-Liners Explained, Part III: All about -redirections</a> -contains some nice visualization to explain bash redirections.</p> -</blockquote> -<h3 id="explanation"><a class="header" href="#explanation">Explanation</a></h3> -<pre><code class="language-bash">j>&i -</code></pre> -<p>Duplicate <code>fd i</code> to <code>fd j</code>, making <code>j</code> a copy of <code>i</code>. See <a href="http://man7.org/linux/man-pages/man2/dup.2.html">dup2(2)</a>.</p> -<p>Example:</p> -<pre><code class="language-bash">command 2>&1 >file -</code></pre> -<ol> -<li>duplicate <code>fd 1</code> to <code>fd 2</code>, effectively redirecting <code>stderr</code> to <code>stdout</code></li> -<li>redirect <code>stdout</code> to <code>file</code></li> -</ol> -<h2 id="process-substitution-ref"><a class="header" href="#process-substitution-ref">Process substitution (<a href="https://tldp.org/LDP/abs/html/process-sub.html">ref</a>)</a></h2> -<p>Process substitution allows to redirect the stdout of multiple processes at -once.</p> -<pre><code class="language-bash">vim -d <(grep foo bar) <(grep foo moose) -</code></pre> -<h2 id="command-grouping"><a class="header" href="#command-grouping">Command grouping</a></h2> -<p>Execute commands in a group with or without subshell. Can be used to easily -redirect stdout/stderr of all commands in the group into one file.</p> -<pre><code class="language-bash"># Group commands without subshell. -v=abc ; { v=foo; echo $v; } ; echo $v -# foo -# foo - -# Group commands with subshell. -v=abc ; ( v=foo; echo $v; ) ; echo $v -# foo -# abc -</code></pre> -<h2 id="argument-parsing-with-getopts"><a class="header" href="#argument-parsing-with-getopts">Argument parsing with <code>getopts</code></a></h2> -<p>The <code>getopts</code> builtin uses following global variables:</p> -<ul> -<li><code>OPTARG</code>, value of last option argument</li> -<li><code>OPTIND</code>, index of the next argument to process (user must reset)</li> -<li><code>OPTERR</code>, display errors if set to <code>1</code></li> -</ul> -<pre><code class="language-bash">getopts <optstring> <param> [<args>] -</code></pre> -<ul> -<li><code><optstring></code> specifies the names of supported options, eg <code>f:c</code> -<ul> -<li><code>f:</code> means <code>-f</code> option with an argument</li> -<li><code>c</code> means <code>-c</code> option without an argument</li> -</ul> -</li> -<li><code><param></code> specifies a variable name which <code>getopts</code> fills with the last parsed option argument</li> -<li><code><args></code> optionally specify argument string to parse, by default <code>getopts</code> parses <code>$@</code></li> -</ul> -<h3 id="example"><a class="header" href="#example">Example</a></h3> -<pre><code class="language-bash">#!/bin/bash -function parse_args() { - while getopts "f:c" PARAM; do - case $PARAM in - f) echo "GOT -f $OPTARG";; - c) echo "GOT -c";; - *) echo "ERR: print usage"; exit 1;; - esac - done - # users responsibility to reset OPTIND - OPTIND=1 -} - -parse_args -f xxx -c -parse_args -f yyy -</code></pre> -<h2 id="regular-expressions"><a class="header" href="#regular-expressions">Regular Expressions</a></h2> -<p>Bash supports regular expression matching with the binary operator <code>=~</code>. -The match results can be accessed via the <code>$BASH_REMATCH</code> variable:</p> -<ul> -<li><code>${BASH_REMATCH[0]}</code> contains the full match</li> -<li><code>${BASH_REMATCH[1]}</code> contains match of the first capture group</li> -</ul> -<pre><code class="language-bash">INPUT='title foo : 1234' -REGEX='^title (.+) : ([0-9]+)$' -if [[ $INPUT =~ $REGEX ]]; then - echo "${BASH_REMATCH[0]}" # title foo : 1234 - echo "${BASH_REMATCH[1]}" # foo - echo "${BASH_REMATCH[2]}" # 1234 -fi -</code></pre> -<blockquote> -<p><strong>Caution</strong>: When specifying a <code>regex</code> in the <code>[[ ]]</code> block directly, quotes will be treated as part of the pattern. -<code>[[ $INPUT =~ "foo" ]]</code> will match against <code>"foo"</code> not <code>foo</code>!</p> -</blockquote> -<h2 id="completion"><a class="header" href="#completion">Completion</a></h2> -<p>The <code>complete</code> builtin is used to interact with the completion system.</p> -<pre><code class="language-bash">complete # print currently installed completion handler -complete -F <func> <cmd> # install <func> as completion handler for <cmd> -complete -r <cmd> # uninstall completion handler for <cmd> -</code></pre> -<p>Variables available in completion functions:</p> -<pre><code class="language-bash"># in -$1 # <cmd> -$2 # current word -$3 # privous word - -COMP_WORDS # array with current command line words -COMP_CWORD # index into COMP_WORDS with current cursor position - -# out -COMPREPLY # array with possible completions -</code></pre> -<p>The <code>compgen</code> builtin is used to generate possible matches by comparing <code>word</code> -against words generated by <code>option</code>.</p> -<pre><code class="language-bash">compgen <option> <word> - -# usefule options: -# -W <list> specify list of possible completions -# -d generate list with dirs -# -f generate list with files -# -u generate list with users -# -e generate list with exported variables - -# compare "f" against words "foo" "foobar" "bar" and generate matches -compgen -W "foo foobar bar" "f" - -# compare "hom" against file/dir names and generate matches -compgen -d -f "hom" -</code></pre> -<h3 id="example-1"><a class="header" href="#example-1">Example</a></h3> -<p>Skeleton to copy/paste for writing simple completions.</p> -<p>Assume a program <code>foo</code> with the following interface:</p> -<pre><code class="language-bash">foo -c green|red|blue -s low|high -f <file> -h -</code></pre> -<p>The completion handler could be implemented as follows:</p> -<pre><code class="language-bash">function _foo() { - local curr=$2 - local prev=$3 - - local opts="-c -s -f -h" - case $prev in - -c) COMPREPLY=( $(compgen -W "green red blue" -- $curr) );; - -s) COMPREPLY=( $(compgen -W "low high" -- $curr) );; - -f) COMPREPLY=( $(compgen -f -- $curr) );; - *) COMPREPLY=( $(compgen -W "$opts" -- $curr) );; - esac -} - -complete -F _foo foo -</code></pre> - - </main> - - <nav class="nav-wrapper" aria-label="Page navigation"> - <!-- Mobile navigation buttons --> - <a rel="prev" href="../tools/zsh.html" class="mobile-nav-chapters previous" title="Previous chapter" aria-label="Previous chapter" aria-keyshortcuts="Left"> - <i class="fa fa-angle-left"></i> - </a> - - <a rel="next prefetch" href="../tools/fish.html" class="mobile-nav-chapters next" title="Next chapter" aria-label="Next chapter" aria-keyshortcuts="Right"> - <i class="fa fa-angle-right"></i> - </a> - - <div style="clear: both"></div> - </nav> - </div> - </div> - - <nav class="nav-wide-wrapper" aria-label="Page navigation"> - <a rel="prev" href="../tools/zsh.html" class="nav-chapters previous" title="Previous chapter" aria-label="Previous chapter" aria-keyshortcuts="Left"> - <i class="fa fa-angle-left"></i> - </a> - - <a rel="next prefetch" href="../tools/fish.html" class="nav-chapters next" title="Next chapter" aria-label="Next chapter" aria-keyshortcuts="Right"> - <i class="fa fa-angle-right"></i> - </a> - </nav> - - </div> - - - - - <script> - window.playground_copyable = true; 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