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<!doctype html><html lang=en class=no-js> <head><meta charset=utf-8><meta name=viewport content="width=device-width,initial-scale=1"><link href=https://flokoe.github.io/bash-hackers-wiki/syntax/expansion/globs/ rel=canonical><link href=../cmdsubst/ rel=prev><link href=../intro/ rel=next><link rel=icon href=../../../assets/images/favicon.png><meta name=generator content="mkdocs-1.6.1, mkdocs-material-9.5.44"><title>Pathname expansion (globbing) - The Bash Hackers Wiki</title><link rel=stylesheet href=../../../assets/stylesheets/main.0253249f.min.css><link rel=stylesheet href=../../../assets/stylesheets/palette.06af60db.min.css><link rel=preconnect href=https://fonts.gstatic.com crossorigin><link rel=stylesheet href="https://fonts.googleapis.com/css?family=Roboto:300,300i,400,400i,700,700i%7CRoboto+Mono:400,400i,700,700i&display=fallback"><style>:root{--md-text-font:"Roboto";--md-code-font:"Roboto Mono"}</style><script>__md_scope=new URL("../../..",location),__md_hash=e=>[...e].reduce(((e,_)=>(e<<5)-e+_.charCodeAt(0)),0),__md_get=(e,_=localStorage,t=__md_scope)=>JSON.parse(_.getItem(t.pathname+"."+e)),__md_set=(e,_,t=localStorage,a=__md_scope)=>{try{t.setItem(a.pathname+"."+e,JSON.stringify(_))}catch(e){}}</script></head> <body dir=ltr data-md-color-scheme=default data-md-color-primary=indigo data-md-color-accent=indigo> <input class=md-toggle data-md-toggle=drawer type=checkbox id=__drawer autocomplete=off> <input class=md-toggle data-md-toggle=search type=checkbox id=__search autocomplete=off> <label class=md-overlay for=__drawer></label> <div data-md-component=skip> <a href=#pathname-expansion-globbing class=md-skip> Skip to content </a> </div> <div data-md-component=announce> </div> <header class=md-header data-md-component=header> <nav class="md-header__inner md-grid" aria-label=Header> <a href=../../.. title="The Bash Hackers Wiki" class="md-header__button md-logo" aria-label="The Bash Hackers Wiki" data-md-component=logo> <svg xmlns=http://www.w3.org/2000/svg viewbox="0 0 24 24"><path d="M12 8a3 3 0 0 0 3-3 3 3 0 0 0-3-3 3 3 0 0 0-3 3 3 3 0 0 0 3 3m0 3.54C9.64 9.35 6.5 8 3 8v11c3.5 0 6.64 1.35 9 3.54 2.36-2.19 5.5-3.54 9-3.54V8c-3.5 0-6.64 1.35-9 3.54"/></svg> </a> <label class="md-header__button md-icon" for=__drawer> <svg xmlns=http://www.w3.org/2000/svg viewbox="0 0 24 24"><path d="M3 6h18v2H3zm0 5h18v2H3zm0 5h18v2H3z"/></svg> </label> <div class=md-header__title data-md-component=header-title> <div class=md-header__ellipsis> <div class=md-header__topic> <span class=md-ellipsis> The Bash Hackers Wiki </span> </div> <div class=md-header__topic data-md-component=header-topic> <span class=md-ellipsis> Pathname expansion (globbing) </span> </div> </div> </div> <form class=md-header__option data-md-component=palette> <input class=md-option data-md-color-media data-md-color-scheme=default data-md-color-primary=indigo data-md-color-accent=indigo aria-label="Switch to dark mode" type=radio name=__palette id=__palette_0> <label class="md-header__button md-icon" title="Switch to dark mode" for=__palette_1 hidden> <svg xmlns=http://www.w3.org/2000/svg viewbox="0 0 24 24"><path d="M12 8a4 4 0 0 0-4 4 4 4 0 0 0 4 4 4 4 0 0 0 4-4 4 4 0 0 0-4-4m0 10a6 6 0 0 1-6-6 6 6 0 0 1 6-6 6 6 0 0 1 6 6 6 6 0 0 1-6 6m8-9.31V4h-4.69L12 .69 8.69 4H4v4.69L.69 12 4 15.31V20h4.69L12 23.31 15.31 20H20v-4.69L23.31 12z"/></svg> </label> <input class=md-option data-md-color-media data-md-color-scheme=slate data-md-color-primary=indigo data-md-color-accent=indigo aria-label="Switch to light mode" type=radio name=__palette id=__palette_1> <label class="md-header__button md-icon" title="Switch to light mode" for=__palette_0 hidden> <svg xmlns=http://www.w3.org/2000/svg viewbox="0 0 24 24"><path d="M12 18c-.89 0-1.74-.2-2.5-.55C11.56 16.5 13 14.42 13 12s-1.44-4.5-3.5-5.45C10.26 6.2 11.11 6 12 6a6 6 0 0 1 6 6 6 6 0 0 1-6 6m8-9.31V4h-4.69L12 .69 8.69 4H4v4.69L.69 12 4 15.31V20h4.69L12 23.31 15.31 20H20v-4.69L23.31 12z"/></svg> </label> </form> <script>var palette=__md_get("__palette");if(palette&&palette.color){if("(prefers-color-scheme)"===palette.color
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</code></pre></div> <p>The base syntax for the pathname expansion is the <a href=../../pattern/ >pattern matching</a> syntax. The pattern you describe is matched against all existing filenames and the matching ones are substituted. Since this substitution happens <strong>after <a href=../wordsplit/ >word splitting</a></strong>, all resulting filenames are literal and treated as separate words, no matter how many spaces or other <code>IFS</code>-characters they contain.</p> <h2 id=normal-behaviour>Normal behaviour<a class=headerlink href=#normal-behaviour title="Permanent link">¶</a></h2> <ul> <li>with <a href=../../../commands/builtin/set/ >the set command</a> (<code>-f</code>, <code>noglob</code>) you can entirely disable pathname expansion</li> <li>when matching a pathname, the slash-character (<code>/</code>) always needs to be matched explicitly</li> <li>the dot at the beginning of a filename must be matched explicitly (also one following a <code>/</code> in the glob)</li> <li>a glob that doesn't match a filename is unchanged and remains what it is</li> </ul> <h2 id=customization>Customization<a class=headerlink href=#customization title="Permanent link">¶</a></h2> <ul> <li>when the shell option <code>nullglob</code> is set, non-matching globs are removed, rather than preserved</li> <li>when the shell option <code>failglob</code> is set, non-matching globs produce an error message and the current command is not executed</li> <li>when the shell option <code>nocaseglob</code> is set, the match is performed case-insensitive</li> <li>when the shell option <code>dotglob</code> is set, wildcard-characters can match a dot at the beginning of a filename</li> <li>when the shell option <code>dirspell</code> is set, Bash performs spelling corrections when matching directory names</li> <li>when the shell option <code>globstar</code> is set, the glob <code>**</code> will recursively match all files and directories. This glob isn't "configurable", i.e. you <strong>can't</strong> do something like <code>**.c</code> to recursively get all <code>*.c</code> filenames.</li> <li>when the shell option <code>globasciiranges</code> is set, the bracket-range globs (e.g. <code>[A-Z]</code>) use C locale order rather than the configured locale's order (i.e. <code>ABC...abc...</code> instead of e.g. <code>AaBbCc...</code>) - since 4.3-alpha</li> <li>the variable <a href=../../shellvars/#GLOBIGNORE>GLOBIGNORE</a> can be set to a colon-separated list of patterns to be removed from the list before it is returned</li> </ul> <h3 id=nullglob>nullglob<a class=headerlink href=#nullglob title="Permanent link">¶</a></h3> <p>Normally, when no glob specified matches an existing filename, no pathname expansion is performed, and the globs are <u><strong>not</strong></u> removed:</p> <div class=highlight><pre><span></span><code>$ echo "Textfiles here:" *.txt
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Textfiles here: *.txt
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</code></pre></div> <p>In this example, no files matched the pattern, so the glob was left intact (a literal asterisk, followed by dot-txt).</p> <p>This can be very annoying, for example when you drive a <a href=../../ccmd/classic_for/ >for-loop</a> using the pathname expansion:</p> <div class=highlight><pre><span></span><code>for filename in *.txt; do
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echo "=== BEGIN: $filename ==="
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cat "$filename"
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echo "=== END: $filename ==="
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done
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</code></pre></div> <p>When no file name matches the glob, the loop will not only output stupid text ("<code>BEGIN: *.txt</code>"), but also will make the <code>cat</code>-command fail with an error, since no file named <code>*.txt</code> exists.</p> <p>Now, when the shell option <code>nullglob</code> is set, Bash will remove the entire glob from the command line. In case of the for-loop here, not even one iteration will be done. It just won't run.</p> <p>So in our first example:</p> <div class=highlight><pre><span></span><code>$ shopt -s nullglob
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$ echo "Textfiles here:" *.txt
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Textfiles here:
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</code></pre></div> <p>and the glob is gone.</p> <h3 id=glob-characters>Glob characters<a class=headerlink href=#glob-characters title="Permanent link">¶</a></h3> <ul> <li><code>*</code> - means \'match any number of characters\'. \'/\' is not matched (and depending on your settings, things like \'.\' may or may not be matched, see above)</li> <li><code>?</code> - means \'match any single character\'</li> <li><code>[abc]</code> - match any of the characters listed. This syntax also supports ranges, like [0-9]</li> </ul> <p>For example, to match something beginning with either \'S\' or \'K\' followed by two numbers, followed by at least 3 more characters:</p> <div class=highlight><pre><span></span><code>[SK][0-9][0-9]???*
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</code></pre></div> <h2 id=see-also>See also<a class=headerlink href=#see-also title="Permanent link">¶</a></h2> <ul> <li><a href=../intro/ >Introduction to expansion and substitution</a></li> <li><a href=../../pattern/ >pattern matching syntax</a></li> <li><a href=../../../commands/builtin/set/ >the set builtin command</a></li> <li><a href=../../../commands/builtin/shopt/ >the shopt builtin command</a></li> <li><a href=../../../internals/shell_options/ >list of shell options</a></li> </ul> <aside class=md-source-file> <span class=md-source-file__fact> <span class=md-icon title="Last update"> <svg xmlns=http://www.w3.org/2000/svg viewbox="0 0 24 24"><path d="M21 13.1c-.1 0-.3.1-.4.2l-1 1 2.1 2.1 1-1c.2-.2.2-.6 0-.8l-1.3-1.3c-.1-.1-.2-.2-.4-.2m-1.9 1.8-6.1 6V23h2.1l6.1-6.1zM12.5 7v5.2l4 2.4-1 1L11 13V7zM11 21.9c-5.1-.5-9-4.8-9-9.9C2 6.5 6.5 2 12 2c5.3 0 9.6 4.1 10 9.3-.3-.1-.6-.2-1-.2s-.7.1-1 .2C19.6 7.2 16.2 4 12 4c-4.4 0-8 3.6-8 8 0 4.1 3.1 7.5 7.1 7.9l-.1.2z"/></svg> </span> <span class="git-revision-date-localized-plugin git-revision-date-localized-plugin-date">November 13, 2024</span> </span> <span class=md-source-file__fact> <span class=md-icon title=Created> <svg xmlns=http://www.w3.org/2000/svg viewbox="0 0 24 24"><path d="M14.47 15.08 11 13V7h1.5v5.25l3.08 1.83c-.41.28-.79.62-1.11 1m-1.39 4.84c-.36.05-.71.08-1.08.08-4.42 0-8-3.58-8-8s3.58-8 8-8 8 3.58 8 8c0 .37-.03.72-.08 1.08.69.1 1.33.32 1.92.64.1-.56.16-1.13.16-1.72 0-5.5-4.5-10-10-10S2 6.5 2 12s4.47 10 10 10c.59 0 1.16-.06 1.72-.16-.32-.59-.54-1.23-.64-1.92M18 15v3h-3v2h3v3h2v-3h3v-2h-3v-3z"/></svg> </span> <span class="git-revision-date-localized-plugin git-revision-date-localized-plugin-date">November 13, 2024</span> </span> </aside> <h2 id=__comments>Comments</h2> <script src=https://giscus.app/client.js data-repo=flokoe/bash-hackers-wiki data-repo-id=R_kgDOJ3Nr6Q data-category="Giscus Page Comments" data-category-id=DIC_kwDOJ3Nr6c4CXq9t data-mapping=pathname data-strict=1 data-reactions-enabled=1 data-emit-metadata=0 data-input-position=top data-theme=preferred_color_scheme data-lang=en data-loading=lazy crossorigin=anonymous async>
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