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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/commands/builtin/echo/ rel=canonical><link href=../declare/ rel=prev><link href=../eval/ rel=next><link rel=icon href=../../../assets/images/favicon.png><meta name=generator content="mkdocs-1.6.1, mkdocs-material-9.5.44"><title>The echo builtin command - 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=#the-echo-builtin-command 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> The echo builtin command </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.media){var medi
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</code></pre></div> <h2 id=description>Description<a class=headerlink href=#description title="Permanent link">¶</a></h2> <p><code>echo</code> outputs it's args to stdout, separated by spaces, followed by a newline. The return status is always <code>0</code>. If the <a href=../shopt/ >shopt</a> option <code>xpg_echo</code> is set, Bash dynamically determines whether echo should expand escape characters (listed below) by default based on the current platform. <code>echo</code> doesn't interpret <code>--</code> as the end of options, and will simply print this string if given.</p> <h3 id=options>Options<a class=headerlink href=#options title="Permanent link">¶</a></h3> <table> <thead> <tr> <th>Option</th> <th>Description</th> </tr> </thead> <tbody> <tr> <td><code>-n</code></td> <td>The trailing newline is suppressed.</td> </tr> <tr> <td><code>-e</code></td> <td>Interpretation of the following backslash-escaped characters (below) is enabled.</td> </tr> <tr> <td><code>-E</code></td> <td>Disables the interpretation of these escape characters, even on systems where they are interpreted by default.</td> </tr> </tbody> </table> <h3 id=escape-sequences>Escape sequences<a class=headerlink href=#escape-sequences title="Permanent link">¶</a></h3> <table> <thead> <tr> <th>Escape</th> <th>Description</th> </tr> </thead> <tbody> <tr> <td><code>\a</code></td> <td>alert (bell)</td> </tr> <tr> <td><code>\b</code></td> <td>backspace</td> </tr> <tr> <td><code>\c</code></td> <td>suppress further output</td> </tr> <tr> <td><code>\e</code></td> <td></td> </tr> <tr> <td><code>\E</code></td> <td>an escape character</td> </tr> <tr> <td><code>\f</code></td> <td>form feed</td> </tr> <tr> <td><code>\n</code></td> <td>new line</td> </tr> <tr> <td><code>\r</code></td> <td>carriage return</td> </tr> <tr> <td><code>\t</code></td> <td>horizontal tab</td> </tr> <tr> <td><code>\v</code></td> <td>vertical tab</td> </tr> <tr> <td><code>\\</code></td> <td>backslash</td> </tr> <tr> <td><code>\0nnn</code></td> <td>the eight-bit character whose value is the octal value nnn (zero to three octal digits)</td> </tr> <tr> <td><code>\xHH</code></td> <td>the eight-bit character whose value is the hexadecimal value HH (one or two hex digits)</td> </tr> <tr> <td><code>\uHHHH</code></td> <td>the Unicode (ISO/IEC 10646) character whose value is the hexadecimal value HHHH (one to four hex digits)</td> </tr> <tr> <td><code>\UHHHHHHHH</code></td> <td>the Unicode (ISO/IEC 10646) character whose value is the hexadecimal value HHHHHHHH (one to eight hex digits)</td> </tr> </tbody> </table> <h2 id=examples>Examples<a class=headerlink href=#examples title="Permanent link">¶</a></h2> <h2 id=portability-considerations>Portability considerations<a class=headerlink href=#portability-considerations title="Permanent link">¶</a></h2> <ul> <li> <p><code>echo</code> is a portability train wreck. No major shell follows POSIX completely, and any shell that attempts to do so should be considered horribly broken. <a href=http://pubs.opengroup.org/onlinepubs/9699919799/utilities/echo.html#tag_20_37>SUSv4</a> specifies that <code>echo</code> <strong>shall not</strong> include any options. Further, it specifies that the behavior of <code>-n</code> as a first argument shall be determined by the implementation, unless XSI is followed, in which case <code>-n</code> is always treated as a string, and backslash escapes are interpreted by default. <code>dash</code> has the misfeature of following this and interpreting escapes by default, but includes a <code>-n</code> feature for suppressing newlines nevertheless.</p> <p>In practice, if you're able to assume a korn-like shell including bash, mksh, or zsh, <code>echo</code> when used in simple cases is generally reliable. For example, in the very common situation in which echo is supplied with a single argument and whose output is to have a newline appended, using <code>echo</code> is considered common practice.</p> </li> <li> <p><strong>Never use options to <code>echo</code>! <em>Ever</em>!</strong> Any time you feel tempted t
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