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</div> </a> <button aria-controls="toc-Usage-sublist" class="cdx-button cdx-button--weight-quiet cdx-button--icon-only vector-toc-toggle"> <span class="vector-icon mw-ui-icon-wikimedia-expand"></span> <span>Toggle Usage subsection</span> </button> <ul id="toc-Usage-sublist" class="vector-toc-list"> <li id="toc-Options" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Options"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.1</span> <span>Options</span> </div> </a> <ul id="toc-Options-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-Use_cases" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Use_cases"> <div class="vector-toc-text"> <span class="vector-toc-numb">3</span> <span>Use cases</span> </div> </a> <ul id="toc-Use_cases-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Examples" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Examples"> <div class="vector-toc-text"> <span class="vector-toc-numb">4</span> <span>Examples</span> </div> </a> <ul id="toc-Examples-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Unix_culture" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Unix_culture"> <div class="vector-toc-text"> <span class="vector-toc-numb">5</span> <span>Unix culture</span> </div> </a> <button aria-controls="toc-Unix_culture-sublist" class="cdx-button cdx-button--weight-quiet cdx-button--icon-only vector-toc-toggle"> <span class="vector-icon mw-ui-icon-wikimedia-expand"></span> <span>Toggle Unix culture subsection</span> </button> <ul id="toc-Unix_culture-sublist" class="vector-toc-list"> <li id="toc-Jargon_file_definition" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Jargon_file_definition"> <div class="vector-toc-text"> <span class="vector-toc-numb">5.1</span> <span>Jargon file definition</span> </div> </a> <ul id="toc-Jargon_file_definition-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Useless_use_of_cat" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Useless_use_of_cat"> <div class="vector-toc-text"> <span class="vector-toc-numb">5.2</span> <span>Useless use of cat</span> </div> </a> <ul id="toc-Useless_use_of_cat-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-See_also" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#See_also"> <div class="vector-toc-text"> <span class="vector-toc-numb">6</span> <span>See also</span> </div> </a> <ul id="toc-See_also-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-References" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#References"> <div class="vector-toc-text"> <span class="vector-toc-numb">7</span> <span>References</span> </div> </a> <ul id="toc-References-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-External_links" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#External_links"> <div class="vector-toc-text"> <span class="vector-toc-numb">8</span> <span>External links</span> </div> </a> <ul id="toc-External_links-sublist" class="vector-toc-list"> </ul> </li> </ul> </div> </div> </nav> </div> </div> <div class="mw-content-container"> <main id="content" class="mw-body"> <header class="mw-body-header vector-page-titlebar"> <nav aria-label="Contents" class="vector-toc-landmark"> <div id="vector-page-titlebar-toc" class="vector-dropdown vector-page-titlebar-toc vector-button-flush-left" > <input type="checkbox" id="vector-page-titlebar-toc-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-page-titlebar-toc" class="vector-dropdown-checkbox " aria-label="Toggle the table of contents" > <label id="vector-page-titlebar-toc-label" for="vector-page-titlebar-toc-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only " aria-hidden="true" ><span class="vector-icon mw-ui-icon-listBullet mw-ui-icon-wikimedia-listBullet"></span> <span class="vector-dropdown-label-text">Toggle the table of contents</span> </label> <div class="vector-dropdown-content"> <div id="vector-page-titlebar-toc-unpinned-container" class="vector-unpinned-container"> </div> </div> </div> </nav> <h1 id="firstHeading" class="firstHeading mw-first-heading">cat (Unix)</h1> <div id="p-lang-btn" class="vector-dropdown mw-portlet mw-portlet-lang" > <input type="checkbox" id="p-lang-btn-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-p-lang-btn" class="vector-dropdown-checkbox mw-interlanguage-selector" aria-label="Go to an article in another language. Available in 34 languages" > <label id="p-lang-btn-label" for="p-lang-btn-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--action-progressive mw-portlet-lang-heading-34" aria-hidden="true" ><span class="vector-icon mw-ui-icon-language-progressive mw-ui-icon-wikimedia-language-progressive"></span> <span class="vector-dropdown-label-text">34 languages</span> </label> <div class="vector-dropdown-content"> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li class="interlanguage-link interwiki-ar mw-list-item"><a href="https://ar.wikipedia.org/wiki/%D9%83%D8%A7%D8%AA_(%D8%A3%D9%85%D8%B1_%D9%8A%D9%88%D9%86%D9%83%D8%B3)" title="كات (أمر يونكس) – Arabic" lang="ar" hreflang="ar" data-title="كات (أمر يونكس)" data-language-autonym="العربية" data-language-local-name="Arabic" class="interlanguage-link-target"><span>العربية</span></a></li><li class="interlanguage-link interwiki-az mw-list-item"><a href="https://az.wikipedia.org/wiki/Cat" title="Cat – Azerbaijani" lang="az" hreflang="az" data-title="Cat" data-language-autonym="Azərbaycanca" data-language-local-name="Azerbaijani" class="interlanguage-link-target"><span>Azərbaycanca</span></a></li><li class="interlanguage-link interwiki-be mw-list-item"><a href="https://be.wikipedia.org/wiki/Cat" title="Cat – Belarusian" lang="be" hreflang="be" data-title="Cat" data-language-autonym="Беларуская" data-language-local-name="Belarusian" class="interlanguage-link-target"><span>Беларуская</span></a></li><li class="interlanguage-link interwiki-ca mw-list-item"><a href="https://ca.wikipedia.org/wiki/Cat_(Unix)" title="Cat (Unix) – Catalan" lang="ca" hreflang="ca" data-title="Cat (Unix)" data-language-autonym="Català" data-language-local-name="Catalan" class="interlanguage-link-target"><span>Català</span></a></li><li class="interlanguage-link interwiki-cs mw-list-item"><a href="https://cs.wikipedia.org/wiki/Cat" title="Cat – Czech" lang="cs" hreflang="cs" data-title="Cat" data-language-autonym="Čeština" data-language-local-name="Czech" class="interlanguage-link-target"><span>Čeština</span></a></li><li class="interlanguage-link interwiki-da mw-list-item"><a href="https://da.wikipedia.org/wiki/Cat_(unix)" title="Cat (unix) – Danish" lang="da" hreflang="da" data-title="Cat (unix)" data-language-autonym="Dansk" data-language-local-name="Danish" class="interlanguage-link-target"><span>Dansk</span></a></li><li class="interlanguage-link interwiki-de mw-list-item"><a href="https://de.wikipedia.org/wiki/Cat_(Unix)" title="Cat (Unix) – German" lang="de" hreflang="de" data-title="Cat (Unix)" data-language-autonym="Deutsch" data-language-local-name="German" class="interlanguage-link-target"><span>Deutsch</span></a></li><li class="interlanguage-link interwiki-el mw-list-item"><a href="https://el.wikipedia.org/wiki/Cat_(Unix)" title="Cat (Unix) – Greek" lang="el" hreflang="el" data-title="Cat (Unix)" data-language-autonym="Ελληνικά" data-language-local-name="Greek" class="interlanguage-link-target"><span>Ελληνικά</span></a></li><li class="interlanguage-link interwiki-es mw-list-item"><a href="https://es.wikipedia.org/wiki/Cat_(Unix)" title="Cat (Unix) – Spanish" lang="es" hreflang="es" data-title="Cat (Unix)" data-language-autonym="Español" data-language-local-name="Spanish" class="interlanguage-link-target"><span>Español</span></a></li><li class="interlanguage-link interwiki-fa mw-list-item"><a href="https://fa.wikipedia.org/wiki/Cat_(%DB%8C%D9%88%D9%86%DB%8C%DA%A9%D8%B3)" title="Cat (یونیکس) – Persian" lang="fa" hreflang="fa" data-title="Cat (یونیکس)" data-language-autonym="فارسی" data-language-local-name="Persian" class="interlanguage-link-target"><span>فارسی</span></a></li><li class="interlanguage-link interwiki-fr mw-list-item"><a href="https://fr.wikipedia.org/wiki/Cat_(Unix)" title="Cat (Unix) – French" lang="fr" hreflang="fr" data-title="Cat (Unix)" data-language-autonym="Français" data-language-local-name="French" class="interlanguage-link-target"><span>Français</span></a></li><li class="interlanguage-link interwiki-ko mw-list-item"><a href="https://ko.wikipedia.org/wiki/Cat_(%EC%9C%A0%EB%8B%89%EC%8A%A4)" title="Cat (유닉스) – Korean" lang="ko" hreflang="ko" data-title="Cat (유닉스)" data-language-autonym="한국어" data-language-local-name="Korean" class="interlanguage-link-target"><span>한국어</span></a></li><li class="interlanguage-link interwiki-hi mw-list-item"><a href="https://hi.wikipedia.org/wiki/%E0%A4%95%E0%A5%88%E0%A4%9F_(%E0%A4%AF%E0%A5%82%E0%A4%A8%E0%A4%BF%E0%A4%95%E0%A5%8D%E0%A4%B8)" title="कैट (यूनिक्स) – Hindi" lang="hi" hreflang="hi" data-title="कैट (यूनिक्स)" data-language-autonym="हिन्दी" data-language-local-name="Hindi" class="interlanguage-link-target"><span>हिन्दी</span></a></li><li class="interlanguage-link interwiki-hr mw-list-item"><a href="https://hr.wikipedia.org/wiki/Cat" title="Cat – Croatian" lang="hr" hreflang="hr" data-title="Cat" data-language-autonym="Hrvatski" data-language-local-name="Croatian" class="interlanguage-link-target"><span>Hrvatski</span></a></li><li class="interlanguage-link interwiki-id mw-list-item"><a href="https://id.wikipedia.org/wiki/Cat_(Unix)" title="Cat (Unix) – Indonesian" lang="id" hreflang="id" data-title="Cat (Unix)" data-language-autonym="Bahasa Indonesia" data-language-local-name="Indonesian" class="interlanguage-link-target"><span>Bahasa Indonesia</span></a></li><li class="interlanguage-link interwiki-it mw-list-item"><a href="https://it.wikipedia.org/wiki/Cat_(Unix)" title="Cat (Unix) – Italian" lang="it" hreflang="it" data-title="Cat (Unix)" data-language-autonym="Italiano" data-language-local-name="Italian" class="interlanguage-link-target"><span>Italiano</span></a></li><li class="interlanguage-link interwiki-he mw-list-item"><a href="https://he.wikipedia.org/wiki/Cat_(%D7%A4%D7%A7%D7%95%D7%93%D7%94)" title="Cat (פקודה) – Hebrew" lang="he" hreflang="he" data-title="Cat (פקודה)" data-language-autonym="עברית" data-language-local-name="Hebrew" class="interlanguage-link-target"><span>עברית</span></a></li><li class="interlanguage-link interwiki-hu mw-list-item"><a href="https://hu.wikipedia.org/wiki/Cat_(Unix)" title="Cat (Unix) – Hungarian" lang="hu" hreflang="hu" data-title="Cat (Unix)" data-language-autonym="Magyar" data-language-local-name="Hungarian" class="interlanguage-link-target"><span>Magyar</span></a></li><li class="interlanguage-link interwiki-ml mw-list-item"><a href="https://ml.wikipedia.org/wiki/%E0%B4%95%E0%B4%BE%E0%B4%B1%E0%B5%8D%E0%B4%B1%E0%B5%8D_(%E0%B4%AF%E0%B5%81%E0%B4%A3%E0%B4%BF%E0%B4%95%E0%B5%8D%E0%B4%B8%E0%B5%8D)" title="കാറ്റ് (യുണിക്സ്) – Malayalam" lang="ml" hreflang="ml" data-title="കാറ്റ് (യുണിക്സ്)" data-language-autonym="മലയാളം" data-language-local-name="Malayalam" class="interlanguage-link-target"><span>മലയാളം</span></a></li><li class="interlanguage-link interwiki-ms mw-list-item"><a href="https://ms.wikipedia.org/wiki/Cat_(UNIX)" title="Cat (UNIX) – Malay" lang="ms" hreflang="ms" data-title="Cat (UNIX)" data-language-autonym="Bahasa Melayu" data-language-local-name="Malay" class="interlanguage-link-target"><span>Bahasa Melayu</span></a></li><li class="interlanguage-link interwiki-nl mw-list-item"><a href="https://nl.wikipedia.org/wiki/Cat_(Unix)" title="Cat (Unix) – Dutch" lang="nl" hreflang="nl" data-title="Cat (Unix)" data-language-autonym="Nederlands" data-language-local-name="Dutch" class="interlanguage-link-target"><span>Nederlands</span></a></li><li class="interlanguage-link interwiki-ja mw-list-item"><a href="https://ja.wikipedia.org/wiki/Cat_(UNIX)" title="Cat (UNIX) – Japanese" lang="ja" hreflang="ja" data-title="Cat (UNIX)" data-language-autonym="日本語" data-language-local-name="Japanese" class="interlanguage-link-target"><span>日本語</span></a></li><li class="interlanguage-link interwiki-uz mw-list-item"><a href="https://uz.wikipedia.org/wiki/Cat_(Unix)" title="Cat (Unix) – Uzbek" lang="uz" hreflang="uz" data-title="Cat (Unix)" data-language-autonym="Oʻzbekcha / ўзбекча" data-language-local-name="Uzbek" class="interlanguage-link-target"><span>Oʻzbekcha / ўзбекча</span></a></li><li class="interlanguage-link interwiki-pl mw-list-item"><a href="https://pl.wikipedia.org/wiki/Cat_(Unix)" title="Cat (Unix) – Polish" lang="pl" hreflang="pl" data-title="Cat (Unix)" data-language-autonym="Polski" data-language-local-name="Polish" class="interlanguage-link-target"><span>Polski</span></a></li><li class="interlanguage-link interwiki-pt mw-list-item"><a href="https://pt.wikipedia.org/wiki/Cat_(Unix)" title="Cat (Unix) – Portuguese" lang="pt" hreflang="pt" data-title="Cat (Unix)" data-language-autonym="Português" data-language-local-name="Portuguese" class="interlanguage-link-target"><span>Português</span></a></li><li class="interlanguage-link interwiki-ro mw-list-item"><a href="https://ro.wikipedia.org/wiki/Cat_(Unix)" title="Cat (Unix) – Romanian" lang="ro" hreflang="ro" data-title="Cat (Unix)" data-language-autonym="Română" data-language-local-name="Romanian" class="interlanguage-link-target"><span>Română</span></a></li><li class="interlanguage-link interwiki-ru mw-list-item"><a href="https://ru.wikipedia.org/wiki/Cat" title="Cat – Russian" lang="ru" hreflang="ru" data-title="Cat" data-language-autonym="Русский" data-language-local-name="Russian" class="interlanguage-link-target"><span>Русский</span></a></li><li class="interlanguage-link interwiki-sk mw-list-item"><a href="https://sk.wikipedia.org/wiki/Cat_(Unix)" title="Cat (Unix) – Slovak" lang="sk" hreflang="sk" data-title="Cat (Unix)" data-language-autonym="Slovenčina" data-language-local-name="Slovak" class="interlanguage-link-target"><span>Slovenčina</span></a></li><li class="interlanguage-link interwiki-sl mw-list-item"><a href="https://sl.wikipedia.org/wiki/Cat_(Unix)" title="Cat (Unix) – Slovenian" lang="sl" hreflang="sl" data-title="Cat (Unix)" data-language-autonym="Slovenščina" data-language-local-name="Slovenian" class="interlanguage-link-target"><span>Slovenščina</span></a></li><li class="interlanguage-link interwiki-sv mw-list-item"><a href="https://sv.wikipedia.org/wiki/Cat" title="Cat – Swedish" lang="sv" hreflang="sv" data-title="Cat" data-language-autonym="Svenska" data-language-local-name="Swedish" class="interlanguage-link-target"><span>Svenska</span></a></li><li class="interlanguage-link interwiki-tr mw-list-item"><a href="https://tr.wikipedia.org/wiki/Cat_(Unix)" title="Cat (Unix) – Turkish" lang="tr" hreflang="tr" data-title="Cat (Unix)" data-language-autonym="Türkçe" data-language-local-name="Turkish" class="interlanguage-link-target"><span>Türkçe</span></a></li><li class="interlanguage-link interwiki-uk mw-list-item"><a href="https://uk.wikipedia.org/wiki/Cat" title="Cat – Ukrainian" lang="uk" hreflang="uk" data-title="Cat" data-language-autonym="Українська" data-language-local-name="Ukrainian" class="interlanguage-link-target"><span>Українська</span></a></li><li class="interlanguage-link interwiki-vi mw-list-item"><a href="https://vi.wikipedia.org/wiki/Cat_(Unix)" title="Cat (Unix) – Vietnamese" lang="vi" hreflang="vi" data-title="Cat (Unix)" data-language-autonym="Tiếng Việt" data-language-local-name="Vietnamese" class="interlanguage-link-target"><span>Tiếng Việt</span></a></li><li class="interlanguage-link interwiki-zh mw-list-item"><a href="https://zh.wikipedia.org/wiki/Cat_(Unix)" title="Cat (Unix) – Chinese" lang="zh" hreflang="zh" data-title="Cat (Unix)" data-language-autonym="中文" data-language-local-name="Chinese" class="interlanguage-link-target"><span>中文</span></a></li> </ul> <div class="after-portlet after-portlet-lang"><span class="wb-langlinks-edit wb-langlinks-link"><a href="https://www.wikidata.org/wiki/Special:EntityPage/Q300918#sitelinks-wikipedia" title="Edit interlanguage links" class="wbc-editpage">Edit links</a></span></div> </div> </div> </div> </header> <div class="vector-page-toolbar"> <div class="vector-page-toolbar-container"> <div id="left-navigation"> <nav aria-label="Namespaces"> <div id="p-associated-pages" class="vector-menu vector-menu-tabs mw-portlet mw-portlet-associated-pages" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="ca-nstab-main" class="selected vector-tab-noicon mw-list-item"><a href="/wiki/Cat_(Unix)" title="View the content page [c]" accesskey="c"><span>Article</span></a></li><li id="ca-talk" class="vector-tab-noicon mw-list-item"><a href="/wiki/Talk:Cat_(Unix)" rel="discussion" title="Discuss improvements to the content page [t]" accesskey="t"><span>Talk</span></a></li> </ul> </div> </div> <div id="vector-variants-dropdown" class="vector-dropdown emptyPortlet" > <input type="checkbox" id="vector-variants-dropdown-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-variants-dropdown" class="vector-dropdown-checkbox " aria-label="Change language 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.hatnote{font-style:italic}.mw-parser-output div.hatnote{padding-left:1.6em;margin-bottom:0.5em}.mw-parser-output .hatnote i{font-style:normal}.mw-parser-output .hatnote+link+.hatnote{margin-top:-0.5em}@media print{body.ns-0 .mw-parser-output .hatnote{display:none!important}}</style><div role="note" class="hatnote navigation-not-searchable">For other uses of cat, see <a href="/wiki/Cat_(disambiguation)" class="mw-disambig" title="Cat (disambiguation)">Cat (disambiguation)</a> and <a href="/wiki/Cat" title="Cat">Cat</a>.</div> <style data-mw-deduplicate="TemplateStyles:r1257001546">.mw-parser-output .infobox-subbox{padding:0;border:none;margin:-3px;width:auto;min-width:100%;font-size:100%;clear:none;float:none;background-color:transparent}.mw-parser-output .infobox-3cols-child{margin:auto}.mw-parser-output .infobox .navbar{font-size:100%}@media screen{html.skin-theme-clientpref-night .mw-parser-output .infobox-full-data:not(.notheme)>div:not(.notheme)[style]{background:#1f1f23!important;color:#f8f9fa}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .infobox-full-data:not(.notheme) div:not(.notheme){background:#1f1f23!important;color:#f8f9fa}}@media(min-width:640px){body.skin--responsive .mw-parser-output .infobox-table{display:table!important}body.skin--responsive .mw-parser-output .infobox-table>caption{display:table-caption!important}body.skin--responsive .mw-parser-output .infobox-table>tbody{display:table-row-group}body.skin--responsive .mw-parser-output .infobox-table tr{display:table-row!important}body.skin--responsive .mw-parser-output .infobox-table th,body.skin--responsive .mw-parser-output .infobox-table td{padding-left:inherit;padding-right:inherit}}</style><table class="infobox vevent"><caption class="infobox-title summary">cat</caption><tbody><tr><td colspan="2" class="infobox-image logo"><span class="mw-default-size" typeof="mw:File/Frameless"><a href="/wiki/File:Cat-example-command.gif" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/e/ec/Cat-example-command.gif/220px-Cat-example-command.gif" decoding="async" width="220" height="129" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/e/ec/Cat-example-command.gif/330px-Cat-example-command.gif 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/e/ec/Cat-example-command.gif/440px-Cat-example-command.gif 2x" data-file-width="1040" data-file-height="608" /></a></span></td></tr><tr><th scope="row" class="infobox-label" style="white-space: nowrap;"><a href="/wiki/Programmer" title="Programmer">Original author(s)</a></th><td class="infobox-data"><a href="/wiki/Ken_Thompson" title="Ken Thompson">Ken Thompson</a>,<br /><a href="/wiki/Dennis_Ritchie" title="Dennis Ritchie">Dennis Ritchie</a></td></tr><tr><th scope="row" class="infobox-label" style="white-space: nowrap;"><a href="/wiki/Programmer" title="Programmer">Developer(s)</a></th><td class="infobox-data"><a href="/wiki/AT%26T_Bell_Laboratories" class="mw-redirect" title="AT&T Bell Laboratories">AT&T Bell Laboratories</a></td></tr><tr><th scope="row" class="infobox-label" style="white-space: nowrap;">Initial release</th><td class="infobox-data">November 3, 1971<span class="noprint">; 53 years ago</span><span style="display:none"> (<span class="bday dtstart published updated">1971-11-03</span>)</span></td></tr><tr><th scope="row" class="infobox-label" style="white-space: nowrap;"><a href="/wiki/Operating_system" title="Operating system">Operating system</a></th><td class="infobox-data"><a href="/wiki/Unix" title="Unix">Unix</a>, <a href="/wiki/Unix-like" title="Unix-like">Unix-like</a>, <a href="/wiki/Plan_9_from_Bell_Labs" title="Plan 9 from Bell Labs">Plan 9</a>, <a href="/wiki/Inferno_(operating_system)" title="Inferno (operating system)">Inferno</a>, <a href="/wiki/ReactOS" title="ReactOS">ReactOS</a></td></tr><tr><th scope="row" class="infobox-label" style="white-space: nowrap;"><a href="/wiki/Computing_platform" title="Computing platform">Platform</a></th><td class="infobox-data"><a href="/wiki/Cross-platform" class="mw-redirect" title="Cross-platform">Cross-platform</a></td></tr><tr><th scope="row" class="infobox-label" style="white-space: nowrap;"><a href="/wiki/Software_categories#Categorization_approaches" title="Software categories">Type</a></th><td class="infobox-data"><a href="/wiki/Command_(computing)" title="Command (computing)">Command</a></td></tr><tr><th scope="row" class="infobox-label" style="white-space: nowrap;"><a href="/wiki/Software_license" title="Software license">License</a></th><td class="infobox-data"><a href="/wiki/Coreutils" class="mw-redirect" title="Coreutils">coreutils</a>: <a href="/wiki/GPLv3%2B" class="mw-redirect" title="GPLv3+">GPLv3+</a><br />ReactOS: <a href="/wiki/GPLv2%2B" class="mw-redirect" title="GPLv2+">GPLv2+</a></td></tr></tbody></table> <p><b><code>cat</code></b> is a standard <a href="/wiki/Unix_utility" class="mw-redirect" title="Unix utility">Unix utility</a> that reads files sequentially, writing them to <a href="/wiki/Standard_output" class="mw-redirect" title="Standard output">standard output</a>. The name is derived from its function to (con)<b>cat</b>enate files (from Latin <i>catenare</i>, "to chain").<sup id="cite_ref-1" class="reference"><a href="#cite_note-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> <sup id="cite_ref-2" class="reference"><a href="#cite_note-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup> It has been ported to a number of operating systems. </p><p>The other primary purpose of <code>cat</code>, aside from concatenation, is file printing — allowing the computer user to view the contents of a file. Printing to files and the terminal are the most common uses of <code>cat</code>.<sup id="cite_ref-PikeKernighan_3-0" class="reference"><a href="#cite_note-PikeKernighan-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup> </p> <meta property="mw:PageProp/toc" /> <div class="mw-heading mw-heading2"><h2 id="History"><span class="anchor" id="tac"></span>History</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Cat_(Unix)&action=edit&section=1" title="Edit section: History"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p><code>cat</code> was part of the early versions of <a href="/wiki/Unix" title="Unix">Unix</a>, e.g., <a href="/wiki/Version_1_Unix" class="mw-redirect" title="Version 1 Unix">Version 1</a>, and replaced <code>pr</code>, a <a href="/wiki/PDP-7" title="PDP-7">PDP-7</a> and <a href="/wiki/Multics" title="Multics">Multics</a> utility for copying a single file to the screen.<sup id="cite_ref-reader_4-0" class="reference"><a href="#cite_note-reader-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup> It was written by <a href="/wiki/Ken_Thompson" title="Ken Thompson">Ken Thompson</a> and <a href="/wiki/Dennis_Ritchie" title="Dennis Ritchie">Dennis Ritchie</a>. The version of <code>cat</code> bundled in <a href="/wiki/GNU" title="GNU">GNU</a> <a href="/wiki/Coreutils" class="mw-redirect" title="Coreutils">coreutils</a> was written by Torbjorn Granlund and <a href="/wiki/Richard_Stallman" title="Richard Stallman">Richard Stallman</a>.<sup id="cite_ref-5" class="reference"><a href="#cite_note-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup> The <a href="/wiki/ReactOS" title="ReactOS">ReactOS</a> version was written by David Welch, Semyon Novikov, and Hermès Bélusca.<sup id="cite_ref-6" class="reference"><a href="#cite_note-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup> </p><p>Over time, alternative utilities such as <code>tac</code> and <code>bat</code> also became available, bringing different new features.<sup id="cite_ref-7" class="reference"><a href="#cite_note-7"><span class="cite-bracket">[</span>7<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-8" class="reference"><a href="#cite_note-8"><span class="cite-bracket">[</span>8<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Usage">Usage</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Cat_(Unix)&action=edit&section=2" title="Edit section: Usage"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The <code>cat</code> utility serves a dual purpose: concatenating and printing. With a single argument, it is often used to print a file to the user's <a href="/wiki/Terminal_emulator" title="Terminal emulator">terminal emulator</a> (or historically to a <a href="/wiki/Computer_terminal" title="Computer terminal">computer terminal</a> or <a href="/wiki/Teletype" class="mw-redirect" title="Teletype">teletype</a>). With more than one argument, it concatenates several files. The combined result is by default also printed to the terminal, but often users <a href="/wiki/Redirection_(computing)" title="Redirection (computing)">redirect</a> the result into yet another file.<sup id="cite_ref-9" class="reference"><a href="#cite_note-9"><span class="cite-bracket">[</span>9<span class="cite-bracket">]</span></a></sup> Hence printing a single file to the terminal is a special use-case of this concatenation program. Yet, this is its most common use.<sup id="cite_ref-PikeKernighan_3-1" class="reference"><a href="#cite_note-PikeKernighan-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup> </p><p>The <a href="/wiki/Single_Unix_Specification" class="mw-redirect" title="Single Unix Specification">Single Unix Specification</a> defines the operation of <code>cat</code> to read files in the sequence given in its arguments, writing their contents to the standard output in the same sequence. The specification mandates the support of one option flag, <i>u</i> for unbuffered output, meaning that each byte is written after it has been read. Some operating systems, like the ones using GNU <a href="/wiki/Coreutils" class="mw-redirect" title="Coreutils">Core Utilities</a>, do this by default and ignore the flag.<sup id="cite_ref-coreutilsman_10-0" class="reference"><a href="#cite_note-coreutilsman-10"><span class="cite-bracket">[</span>10<span class="cite-bracket">]</span></a></sup> </p><p>If one of the input filenames is specified as a single hyphen (<i>-</i>), then <code>cat</code> reads from standard input at that point in the sequence. If no files are specified, <code>cat</code> reads from standard input only. </p><p>The command-<a href="/wiki/Syntax" title="Syntax">syntax</a> is: </p> <pre>cat [options] [file_names] </pre> <div class="mw-heading mw-heading3"><h3 id="Options">Options</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Cat_(Unix)&action=edit&section=3" title="Edit section: Options"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Example of some <code>cat</code> options:<sup id="cite_ref-11" class="reference"><a href="#cite_note-11"><span class="cite-bracket">[</span>11<span class="cite-bracket">]</span></a></sup> </p> <ul><li><style data-mw-deduplicate="TemplateStyles:r1239335663">.mw-parser-output .mw-tmpl-kbd{background:#EEE;color:var(--color-base)}@media screen{html.skin-theme-clientpref-night .mw-parser-output .mw-tmpl-kbd{background:#171a1d}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .mw-tmpl-kbd{background:#171a1d}}</style><kbd class="mw-tmpl-kbd" style="letter-spacing:0.05em; padding-left:0.25em; padding-right:0.2em;">-b</kbd> (GNU: <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1239335663"><kbd class="mw-tmpl-kbd" style="letter-spacing:0.05em; padding-left:0.25em; padding-right:0.2em;">--number-nonblank</kbd>), number non-blank output lines</li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1239335663"><kbd class="mw-tmpl-kbd" style="letter-spacing:0.05em; padding-left:0.25em; padding-right:0.2em;">-e</kbd> implies <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1239335663"><kbd class="mw-tmpl-kbd" style="letter-spacing:0.05em; padding-left:0.25em; padding-right:0.2em;">-v</kbd> but also display end-of-line characters as <samp style="padding-left:0.4em; padding-right:0.4em; color:var( --color-subtle, #666666);">$</samp> (GNU only: <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1239335663"><kbd class="mw-tmpl-kbd" style="letter-spacing:0.05em; padding-left:0.25em; padding-right:0.2em;">-E</kbd> the same, but without implying <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1239335663"><kbd class="mw-tmpl-kbd" style="letter-spacing:0.05em; padding-left:0.25em; padding-right:0.2em;">-v</kbd>)</li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1239335663"><kbd class="mw-tmpl-kbd" style="letter-spacing:0.05em; padding-left:0.25em; padding-right:0.2em;">-n</kbd> (GNU: <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1239335663"><kbd class="mw-tmpl-kbd" style="letter-spacing:0.05em; padding-left:0.25em; padding-right:0.2em;">--number</kbd>), number all output lines</li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1239335663"><kbd class="mw-tmpl-kbd" style="letter-spacing:0.05em; padding-left:0.25em; padding-right:0.2em;">-s</kbd> (GNU: <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1239335663"><kbd class="mw-tmpl-kbd" style="letter-spacing:0.05em; padding-left:0.25em; padding-right:0.2em;">--squeeze-blank</kbd>), squeeze multiple adjacent blank lines</li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1239335663"><kbd class="mw-tmpl-kbd" style="letter-spacing:0.05em; padding-left:0.25em; padding-right:0.2em;">-t</kbd> implies <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1239335663"><kbd class="mw-tmpl-kbd" style="letter-spacing:0.05em; padding-left:0.25em; padding-right:0.2em;">-v</kbd>, but also display tabs as <samp style="padding-left:0.4em; padding-right:0.4em; color:var( --color-subtle, #666666);">^I</samp> (GNU: <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1239335663"><kbd class="mw-tmpl-kbd" style="letter-spacing:0.05em; padding-left:0.25em; padding-right:0.2em;">-T</kbd> the same, but without implying <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1239335663"><kbd class="mw-tmpl-kbd" style="letter-spacing:0.05em; padding-left:0.25em; padding-right:0.2em;">-v</kbd>)</li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1239335663"><kbd class="mw-tmpl-kbd" style="letter-spacing:0.05em; padding-left:0.25em; padding-right:0.2em;">-u</kbd> use unbuffered I/O for stdout. POSIX does not specify the behavior without this option.</li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1239335663"><kbd class="mw-tmpl-kbd" style="letter-spacing:0.05em; padding-left:0.25em; padding-right:0.2em;">-v</kbd> (GNU: <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1239335663"><kbd class="mw-tmpl-kbd" style="letter-spacing:0.05em; padding-left:0.25em; padding-right:0.2em;">--show-nonprinting</kbd>), displays nonprinting characters, except for tabs and the end of line character</li></ul> <div class="mw-heading mw-heading2"><h2 id="Use_cases">Use cases</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Cat_(Unix)&action=edit&section=4" title="Edit section: Use cases"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p><code>cat</code> can be used to pipe a file to a program that expects plain text or binary data on its input stream. <code>cat</code> does not destroy non-text bytes when concatenating and outputting. As such, its two main use cases are text files and certain format-compatible types of binary files. </p><p>Concatenation of text is limited to text files using the same legacy encoding, such as <a href="/wiki/ASCII" title="ASCII">ASCII</a>. <code>cat</code> does not provide a way to concatenate Unicode text files that have a <a href="/wiki/Byte_Order_Mark" class="mw-redirect" title="Byte Order Mark">Byte Order Mark</a> or files using different text encodings from each other. </p><p>For many structured binary data sets, the resulting combined file may not be valid; for example, if a file has a unique header or footer, the result will spuriously duplicate these. However, for some multimedia <a href="/wiki/Digital_container_format" class="mw-redirect" title="Digital container format">digital container formats</a>, the resulting file is valid, and so <code>cat</code> provides an effective means of appending files. Video streams can be a significant example of files that <code>cat</code> can concatenate without issue, e.g. the <a href="/wiki/MPEG_program_stream" title="MPEG program stream">MPEG program stream</a> (MPEG-1 and MPEG-2) and <a href="/wiki/DV_(video_format)" title="DV (video format)">DV</a> (Digital Video) formats, which are fundamentally simple streams of packets. </p> <div class="mw-heading mw-heading2"><h2 id="Examples">Examples</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Cat_(Unix)&action=edit&section=5" title="Edit section: Examples"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <table class="wikitable"> <tbody><tr> <th><kbd>Command</kbd></th> <th>Explanation </th></tr> <tr> <td><kbd>cat file1.txt </kbd></td> <td>Display contents of file </td></tr> <tr> <td><kbd>cat file1.txt file2.txt</kbd></td> <td>Concatenate two text files and display the result in the terminal </td></tr> <tr> <td><kbd>cat file1.txt file2.txt > newcombinedfile.txt</kbd></td> <td>Concatenate two text files and write them to a new file </td></tr> <tr> <td><kbd>cat >newfile.txt</kbd></td> <td>Create a file called newfile.txt. Type the desired input and press CTRL+D to finish. The text will be in file newfile.txt. </td></tr> <tr> <td><kbd>cat -n file1.txt file2.txt > newnumberedfile.txt</kbd></td> <td>Some implementations of cat, with option -n, can also number lines </td></tr> <tr> <td><kbd>cat file1.txt > file2.txt</kbd></td> <td>Copy the contents of file1.txt into file2.txt </td></tr> <tr> <td><kbd>cat file1.txt >> file2.txt</kbd></td> <td>Append the contents of file1.txt to file2.txt </td></tr> <tr> <td><kbd>cat file1.txt file2.txt file3.txt | sort > test4</kbd></td> <td>Concatenate the files, sort the complete set of lines, and write the output to a newly created file </td></tr> <tr> <td><kbd>cat file1.txt file2.txt | less</kbd></td> <td>Run the program "less" with the concatenation of file1 and file2 as its input </td></tr> <tr> <td><kbd>cat file1.txt | grep example</kbd></td> <td>Highlight instances the word "example" in file1.txt </td></tr> <tr> <td><kbd>command | cat</kbd></td> <td>Cancel "command" special behavior (e.g. paging) when it writes directly to TTY (cf. UUOC below) </td></tr> </tbody></table> <div class="mw-heading mw-heading2"><h2 id="Unix_culture">Unix culture</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Cat_(Unix)&action=edit&section=6" title="Edit section: Unix culture"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <div class="mw-heading mw-heading3"><h3 id="Jargon_file_definition">Jargon file definition</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Cat_(Unix)&action=edit&section=7" title="Edit section: Jargon file definition"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The <a href="/wiki/Jargon_File" title="Jargon File">Jargon File</a> version 4.4.7 lists this as the definition of <code>cat</code>: </p> <style data-mw-deduplicate="TemplateStyles:r1244412712">.mw-parser-output .templatequote{overflow:hidden;margin:1em 0;padding:0 32px}.mw-parser-output .templatequotecite{line-height:1.5em;text-align:left;margin-top:0}@media(min-width:500px){.mw-parser-output .templatequotecite{padding-left:1.6em}}</style><blockquote class="templatequote"> <ol><li>To spew an entire file to the screen or some other output sink without pause (syn. blast).</li> <li>By extension, to dump large amounts of data at an unprepared target or with no intention of browsing it carefully. Usage: considered silly. Rare outside Unix sites. See also <kbd><a href="/wiki/Dd_(Unix)" title="Dd (Unix)">dd</a></kbd>, <a href="/w/index.php?title=Block-transfer_instruction&action=edit&redlink=1" class="new" title="Block-transfer instruction (page does not exist)">BLT</a>.</li></ol> <p>Among Unix fans, <kbd>cat(1)</kbd> is considered an excellent example of <a href="/wiki/User_interface" title="User interface">user-interface</a> design, because it delivers the file contents without such verbosity as spacing or headers between the files, and because it does not require the files to consist of lines of text, but works with any sort of data. </p><p>Among Unix critics, <kbd>cat(1)</kbd> is considered the canonical example of bad user-interface design, because of its woefully unobvious name. It is far more often used to blast a single file to <a href="/wiki/Standard_output" class="mw-redirect" title="Standard output">standard output</a> than to concatenate two or more files. The name <kbd>cat</kbd> for the former operation is just as unintuitive as, say, <a href="/wiki/Lisp_programming_language" class="mw-redirect" title="Lisp programming language">LISP</a>'s <kbd><a href="/wiki/CAR_and_CDR" title="CAR and CDR">cdr</a></kbd>.<sup class="noprint Inline-Template Template-Fact" style="white-space:nowrap;">[<i><a href="/wiki/Wikipedia:Citation_needed" title="Wikipedia:Citation needed"><span title="Both are matters of Opinion (August 2021)">citation needed</span></a></i>]</sup> </p> </blockquote> <div class="mw-heading mw-heading3"><h3 id="Useless_use_of_cat">Useless use of cat</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Cat_(Unix)&action=edit&section=8" title="Edit section: Useless use of cat"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p><i>Useless use of cat</i> (<i>UUOC</i>) is common Unix jargon for command line constructs that only provide a function of convenience to the user.<sup id="cite_ref-:0_12-0" class="reference"><a href="#cite_note-:0-12"><span class="cite-bracket">[</span>12<span class="cite-bracket">]</span></a></sup> In computing, the word "abuse",<sup id="cite_ref-13" class="reference"><a href="#cite_note-13"><span class="cite-bracket">[</span>13<span class="cite-bracket">]</span></a></sup> in the second sense of the definition, is used to disparage the excessive or unnecessary use of a language construct; thus, abuse of <style data-mw-deduplicate="TemplateStyles:r886049734">.mw-parser-output .monospaced{font-family:monospace,monospace}</style><span class="monospaced">cat</span> is sometimes called "cat abuse". Example of a common <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r886049734"><span class="monospaced">cat</span> abuse is given in the award: </p> <pre>cat filename | command arg1 arg2 argn </pre> <p>This can be rewritten using <a href="/wiki/Redirection_(computing)" title="Redirection (computing)">redirection</a> of <a href="/wiki/Stdin" class="mw-redirect" title="Stdin">stdin</a> instead, in either of the following forms (the first is more traditional): </p> <pre>command arg1 arg2 argn < filename </pre> <pre><filename command arg1 arg2 argn </pre> <p>Beyond other benefits, the input redirection forms allow <i>command</i> to perform <a href="/wiki/Random_access" title="Random access">random access</a> on the file, whereas the <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r886049734"><span class="monospaced">cat</span> examples do not. This is because the redirection form opens the file as the stdin file descriptor which <i>command</i> can fully access, while the <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r886049734"><span class="monospaced">cat</span> form simply provides the data as a stream of bytes. </p><p>Another common case where <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r886049734"><span class="monospaced">cat</span> is unnecessary is where a command defaults to operating on stdin, but will read from a file, if the filename is given as an argument. This is the case for many common commands; the following examples </p> <pre>cat file | grep pattern </pre> <pre>cat file | less </pre> <p>can instead be written as </p> <pre>grep pattern file </pre> <pre>less file </pre> <p>A common interactive use of <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r886049734"><span class="monospaced">cat</span> for a single file is to output the content of a file to standard output. However, if the output is piped or redirected, <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r886049734"><span class="monospaced">cat</span> is unnecessary. </p><p>A <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r886049734"><span class="monospaced">cat</span> written with UUOC might still be preferred for readability reasons, as reading a piped stream left-to-right might be easier to conceptualize.<sup id="cite_ref-14" class="reference"><a href="#cite_note-14"><span class="cite-bracket">[</span>14<span class="cite-bracket">]</span></a></sup> Also, one wrong use of the redirection symbol <span class="nounderlines" style="border: 1px solid var(--border-color-muted,#ddd); color: var(--color-base); background-color: var( --background-color-neutral-subtle, #fdfdfd); padding: 1px 1px;">></span> instead of <span class="nounderlines" style="border: 1px solid var(--border-color-muted,#ddd); color: var(--color-base); background-color: var( --background-color-neutral-subtle, #fdfdfd); padding: 1px 1px;"><</span> (often adjacent on keyboards) may permanently delete the content of a file, in other words <a href="/wiki/Clobbering" title="Clobbering">clobbering</a>, and one way to avoid this is to use <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r886049734"><span class="monospaced">cat</span> with pipes. Compare: </p> <pre>command < in | command2 > out </pre> <pre><in command | command2 > out </pre> <p>with: </p> <pre>cat in | command | command2 > out </pre> <div class="mw-heading mw-heading2"><h2 id="See_also">See also</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Cat_(Unix)&action=edit&section=9" title="Edit section: See also"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><a href="/wiki/Paste_(Unix)" title="Paste (Unix)">paste</a></li> <li><a href="/wiki/Split_(Unix)" title="Split (Unix)">split</a>, a command that splits a file into pieces which cat can then rejoin.</li> <li><a href="/wiki/Zcat" class="mw-redirect" title="Zcat">zcat</a></li> <li><a href="/wiki/Less_(Unix)" title="Less (Unix)">less</a></li> <li><a href="/wiki/Netcat" title="Netcat">netcat</a> – Computer networking utility</li></ul> <div class="mw-heading mw-heading2"><h2 id="References">References</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Cat_(Unix)&action=edit&section=10" title="Edit section: References"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1239543626">.mw-parser-output .reflist{margin-bottom:0.5em;list-style-type:decimal}@media screen{.mw-parser-output .reflist{font-size:90%}}.mw-parser-output .reflist .references{font-size:100%;margin-bottom:0;list-style-type:inherit}.mw-parser-output .reflist-columns-2{column-width:30em}.mw-parser-output .reflist-columns-3{column-width:25em}.mw-parser-output .reflist-columns{margin-top:0.3em}.mw-parser-output .reflist-columns ol{margin-top:0}.mw-parser-output .reflist-columns li{page-break-inside:avoid;break-inside:avoid-column}.mw-parser-output .reflist-upper-alpha{list-style-type:upper-alpha}.mw-parser-output .reflist-upper-roman{list-style-type:upper-roman}.mw-parser-output .reflist-lower-alpha{list-style-type:lower-alpha}.mw-parser-output .reflist-lower-greek{list-style-type:lower-greek}.mw-parser-output .reflist-lower-roman{list-style-type:lower-roman}</style><div class="reflist"> <div class="mw-references-wrap mw-references-columns"><ol class="references"> <li id="cite_note-1"><span class="mw-cite-backlink"><b><a href="#cite_ref-1">^</a></b></span> <span class="reference-text"><style data-mw-deduplicate="TemplateStyles:r1238218222">.mw-parser-output cite.citation{font-style:inherit;word-wrap:break-word}.mw-parser-output .citation q{quotes:"\"""\"""'""'"}.mw-parser-output .citation:target{background-color:rgba(0,127,255,0.133)}.mw-parser-output .id-lock-free.id-lock-free a{background:url("//upload.wikimedia.org/wikipedia/commons/6/65/Lock-green.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-limited.id-lock-limited a,.mw-parser-output .id-lock-registration.id-lock-registration a{background:url("//upload.wikimedia.org/wikipedia/commons/d/d6/Lock-gray-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-subscription.id-lock-subscription a{background:url("//upload.wikimedia.org/wikipedia/commons/a/aa/Lock-red-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .cs1-ws-icon a{background:url("//upload.wikimedia.org/wikipedia/commons/4/4c/Wikisource-logo.svg")right 0.1em center/12px no-repeat}body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-free a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-limited a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-registration a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-subscription a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .cs1-ws-icon a{background-size:contain;padding:0 1em 0 0}.mw-parser-output .cs1-code{color:inherit;background:inherit;border:none;padding:inherit}.mw-parser-output .cs1-hidden-error{display:none;color:var(--color-error,#d33)}.mw-parser-output .cs1-visible-error{color:var(--color-error,#d33)}.mw-parser-output .cs1-maint{display:none;color:#085;margin-left:0.3em}.mw-parser-output .cs1-kern-left{padding-left:0.2em}.mw-parser-output .cs1-kern-right{padding-right:0.2em}.mw-parser-output .citation .mw-selflink{font-weight:inherit}@media screen{.mw-parser-output .cs1-format{font-size:95%}html.skin-theme-clientpref-night .mw-parser-output .cs1-maint{color:#18911f}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .cs1-maint{color:#18911f}}</style><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://kb.iu.edu/d/abnd">"In Unix, what do some obscurely named commands stand for?"</a>. <i>University Information Technology Services</i>. Indiana University.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=University+Information+Technology+Services&rft.atitle=In+Unix%2C+what+do+some+obscurely+named+commands+stand+for%3F&rft_id=https%3A%2F%2Fkb.iu.edu%2Fd%2Fabnd&rfr_id=info%3Asid%2Fen.wikipedia.org%3ACat+%28Unix%29" class="Z3988"></span></span> </li> <li id="cite_note-2"><span class="mw-cite-backlink"><b><a href="#cite_ref-2">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFKernighanPike1984" class="citation book cs1">Kernighan, Brian W.; Pike, Rob (1984). <i>The UNIX Programming Environment</i>. Addison-Wesley. p. 15.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=The+UNIX+Programming+Environment&rft.pages=15&rft.pub=Addison-Wesley&rft.date=1984&rft.aulast=Kernighan&rft.aufirst=Brian+W.&rft.au=Pike%2C+Rob&rfr_id=info%3Asid%2Fen.wikipedia.org%3ACat+%28Unix%29" class="Z3988"></span></span> </li> <li id="cite_note-PikeKernighan-3"><span class="mw-cite-backlink">^ <a href="#cite_ref-PikeKernighan_3-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-PikeKernighan_3-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFPikeKernighan" class="citation report cs1"><a href="/wiki/Rob_Pike" title="Rob Pike">Pike, Rob</a>; <a href="/wiki/Brian_Kernighan" title="Brian Kernighan">Kernighan, Brian W.</a> <a rel="nofollow" class="external text" href="http://harmful.cat-v.org/cat-v/unix_prog_design.pdf">Program design in the UNIX environment</a> <span class="cs1-format">(PDF)</span> (Report). p. 3.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=report&rft.btitle=Program+design+in+the+UNIX+environment&rft.pages=3&rft.aulast=Pike&rft.aufirst=Rob&rft.au=Kernighan%2C+Brian+W.&rft_id=http%3A%2F%2Fharmful.cat-v.org%2Fcat-v%2Funix_prog_design.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3ACat+%28Unix%29" class="Z3988"></span></span> </li> <li id="cite_note-reader-4"><span class="mw-cite-backlink"><b><a href="#cite_ref-reader_4-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFMcIlroy1987" class="citation techreport cs1"><a href="/wiki/Doug_McIlroy" class="mw-redirect" title="Doug McIlroy">McIlroy, M. D.</a> (1987). <a rel="nofollow" class="external text" href="http://www.cs.dartmouth.edu/~doug/reader.pdf"><i>A Research Unix reader: annotated excerpts from the Programmer's Manual, 1971–1986</i></a> <span class="cs1-format">(PDF)</span> (Technical report). CSTR. Bell Labs. 139.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=report&rft.btitle=A+Research+Unix+reader%3A+annotated+excerpts+from+the+Programmer%27s+Manual%2C+1971%E2%80%931986&rft.series=CSTR&rft.pub=Bell+Labs&rft.date=1987&rft.aulast=McIlroy&rft.aufirst=M.+D.&rft_id=http%3A%2F%2Fwww.cs.dartmouth.edu%2F~doug%2Freader.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3ACat+%28Unix%29" class="Z3988"></span></span> </li> <li id="cite_note-5"><span class="mw-cite-backlink"><b><a href="#cite_ref-5">^</a></b></span> <span class="reference-text"><span class="plainlinksneverexpand"><code><a rel="nofollow" class="external text" href="https://linux.die.net/man/1/cat">cat(1)</a></code></span> – <a href="/wiki/Linux" title="Linux">Linux</a> User Commands <a href="/wiki/Man_page" title="Man page">Manual</a></span> </li> <li id="cite_note-6"><span class="mw-cite-backlink"><b><a href="#cite_ref-6">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://github.com/reactos/reactos/blob/master/modules/rosapps/applications/cmdutils/cat/cat.c">"reactos/cat.c at master · reactos/reactos · GitHub"</a>. <i>github.com</i><span class="reference-accessdate">. Retrieved <span class="nowrap">August 28,</span> 2021</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=github.com&rft.atitle=reactos%2Fcat.c+at+master+%C2%B7+reactos%2Freactos+%C2%B7+GitHub&rft_id=https%3A%2F%2Fgithub.com%2Freactos%2Freactos%2Fblob%2Fmaster%2Fmodules%2Frosapps%2Fapplications%2Fcmdutils%2Fcat%2Fcat.c&rfr_id=info%3Asid%2Fen.wikipedia.org%3ACat+%28Unix%29" class="Z3988"></span></span> </li> <li id="cite_note-7"><span class="mw-cite-backlink"><b><a href="#cite_ref-7">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://man7.org/linux/man-pages/man1/tac.1.html">"tac(1) - Linux manual page"</a>. <i>man7.org</i>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=man7.org&rft.atitle=tac%281%29+-+Linux+manual+page&rft_id=https%3A%2F%2Fman7.org%2Flinux%2Fman-pages%2Fman1%2Ftac.1.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3ACat+%28Unix%29" class="Z3988"></span></span> </li> <li id="cite_note-8"><span class="mw-cite-backlink"><b><a href="#cite_ref-8">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://github.com/sharkdp/bat">"sharkdp/bat"</a>. December 2, 2021 – via GitHub.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=sharkdp%2Fbat&rft.date=2021-12-02&rft_id=https%3A%2F%2Fgithub.com%2Fsharkdp%2Fbat&rfr_id=info%3Asid%2Fen.wikipedia.org%3ACat+%28Unix%29" class="Z3988"></span></span> </li> <li id="cite_note-9"><span class="mw-cite-backlink"><b><a href="#cite_ref-9">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation report cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20060617103249/http://www.bitsavers.org/pdf/bellLabs/unix/UNIX_ProgrammersManual_Nov71.pdf">UNIX programmers manual</a> <span class="cs1-format">(PDF)</span>. <i>bitsavers.org</i> (Report). November 3, 1971. p. 32. Archived from <a rel="nofollow" class="external text" href="http://www.bitsavers.org/pdf/bellLabs/unix/UNIX_ProgrammersManual_Nov71.pdf">the original</a> <span class="cs1-format">(PDF)</span> on 2006-06-17.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=report&rft.btitle=UNIX+programmers+manual&rft.pages=32&rft.date=1971-11-03&rft_id=http%3A%2F%2Fwww.bitsavers.org%2Fpdf%2FbellLabs%2Funix%2FUNIX_ProgrammersManual_Nov71.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3ACat+%28Unix%29" class="Z3988"></span></span> </li> <li id="cite_note-coreutilsman-10"><span class="mw-cite-backlink"><b><a href="#cite_ref-coreutilsman_10-0">^</a></b></span> <span class="reference-text">GNU Coreutils. <a rel="nofollow" class="external text" href="https://www.gnu.org/software/coreutils/manual/html_node/cat-invocation.html">"GNU Coreutils manual"</a>, <i><a href="/wiki/GNU" title="GNU">GNU</a></i>, Retrieved on 1 Mars 2017.</span> </li> <li id="cite_note-11"><span class="mw-cite-backlink"><b><a href="#cite_ref-11">^</a></b></span> <span class="reference-text"><a href="/wiki/OpenBSD" title="OpenBSD">OpenBSD</a> manual page and the GNU Core Utiltites version of cat</span> </li> <li id="cite_note-:0-12"><span class="mw-cite-backlink"><b><a href="#cite_ref-:0_12-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFBrian_Blackmore1994" class="citation newsgroup cs1">Brian Blackmore (1994-12-05). <a rel="nofollow" class="external text" href="https://groups.google.com/g/comp.unix.shell/c/532AcI3-zs4/m/SqJ1RQzXdZ4J">"Perl or Sed?"</a>. <a href="/wiki/Usenet_newsgroup" title="Usenet newsgroup">Newsgroup</a>: <a rel="nofollow" class="external text" href="news:comp.unix.shell">comp.unix.shell</a><span class="reference-accessdate">. Retrieved <span class="nowrap">2024-02-12</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Perl+or+Sed%3F&rft.pub=comp.unix.shell&rft.date=1994-12-05&rft.au=Brian+Blackmore&rft_id=https%3A%2F%2Fgroups.google.com%2Fg%2Fcomp.unix.shell%2Fc%2F532AcI3-zs4%2Fm%2FSqJ1RQzXdZ4J&rfr_id=info%3Asid%2Fen.wikipedia.org%3ACat+%28Unix%29" class="Z3988"></span></span> </li> <li id="cite_note-13"><span class="mw-cite-backlink"><b><a href="#cite_ref-13">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://www.merriam-webster.com/dictionary/abuse">"Merriam Webster's Definition of Abuse"</a><span class="reference-accessdate">. Retrieved <span class="nowrap">2021-02-25</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Merriam+Webster%27s+Definition+of+Abuse&rft_id=https%3A%2F%2Fwww.merriam-webster.com%2Fdictionary%2Fabuse&rfr_id=info%3Asid%2Fen.wikipedia.org%3ACat+%28Unix%29" class="Z3988"></span></span> </li> <li id="cite_note-14"><span class="mw-cite-backlink"><b><a href="#cite_ref-14">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFNguyen" class="citation web cs1">Nguyen, Dan. <a rel="nofollow" class="external text" href="http://www.compciv.org/topics/bash/pipes-and-redirection/">"Stanford Computational Journalism Lab"</a>. stanford.edu<span class="reference-accessdate">. Retrieved <span class="nowrap">2017-10-08</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Stanford+Computational+Journalism+Lab&rft.pub=stanford.edu&rft.aulast=Nguyen&rft.aufirst=Dan&rft_id=http%3A%2F%2Fwww.compciv.org%2Ftopics%2Fbash%2Fpipes-and-redirection%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3ACat+%28Unix%29" class="Z3988"></span></span> </li> </ol></div></div> <div class="mw-heading mw-heading2"><h2 id="External_links">External links</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Cat_(Unix)&action=edit&section=11" title="Edit section: External links"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1235681985">.mw-parser-output .side-box{margin:4px 0;box-sizing:border-box;border:1px solid #aaa;font-size:88%;line-height:1.25em;background-color:var(--background-color-interactive-subtle,#f8f9fa);display:flow-root}.mw-parser-output .side-box-abovebelow,.mw-parser-output .side-box-text{padding:0.25em 0.9em}.mw-parser-output .side-box-image{padding:2px 0 2px 0.9em;text-align:center}.mw-parser-output .side-box-imageright{padding:2px 0.9em 2px 0;text-align:center}@media(min-width:500px){.mw-parser-output .side-box-flex{display:flex;align-items:center}.mw-parser-output .side-box-text{flex:1;min-width:0}}@media(min-width:720px){.mw-parser-output .side-box{width:238px}.mw-parser-output .side-box-right{clear:right;float:right;margin-left:1em}.mw-parser-output .side-box-left{margin-right:1em}}</style><style data-mw-deduplicate="TemplateStyles:r1237033735">@media print{body.ns-0 .mw-parser-output .sistersitebox{display:none!important}}@media screen{html.skin-theme-clientpref-night .mw-parser-output .sistersitebox img[src*="Wiktionary-logo-en-v2.svg"]{background-color:white}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .sistersitebox img[src*="Wiktionary-logo-en-v2.svg"]{background-color:white}}</style><div class="side-box side-box-right plainlinks sistersitebox"><style data-mw-deduplicate="TemplateStyles:r1126788409">.mw-parser-output .plainlist ol,.mw-parser-output .plainlist ul{line-height:inherit;list-style:none;margin:0;padding:0}.mw-parser-output .plainlist ol li,.mw-parser-output .plainlist ul li{margin-bottom:0}</style> <div class="side-box-flex"> <div class="side-box-image"><span class="noviewer" typeof="mw:File"><span><img alt="" src="//upload.wikimedia.org/wikipedia/commons/thumb/d/df/Wikibooks-logo-en-noslogan.svg/40px-Wikibooks-logo-en-noslogan.svg.png" decoding="async" width="40" height="40" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/d/df/Wikibooks-logo-en-noslogan.svg/60px-Wikibooks-logo-en-noslogan.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/d/df/Wikibooks-logo-en-noslogan.svg/80px-Wikibooks-logo-en-noslogan.svg.png 2x" data-file-width="400" data-file-height="400" /></span></span></div> <div class="side-box-text plainlist">The Wikibook <i><a href="https://en.wikibooks.org/wiki/Guide_to_Unix" class="extiw" title="wikibooks:Guide to Unix">Guide to Unix</a></i> has a page on the topic of: <i><b><a href="https://en.wikibooks.org/wiki/Guide_to_Unix/Commands" class="extiw" title="wikibooks:Guide to Unix/Commands">Commands</a></b></i></div></div> </div> <ul><li><span class="plainlinksneverexpand"><code><a rel="nofollow" class="external text" href="https://pubs.opengroup.org/onlinepubs/9799919799/utilities/cat.html">cat</a></code></span>: concatenate and print files – Shell and Utilities Reference, <a href="/wiki/Single_Unix_Specification" class="mw-redirect" title="Single Unix Specification">The Single UNIX Specification</a>, Version 4 from <a href="/wiki/The_Open_Group" title="The Open Group">The Open Group</a></li> <li><a rel="nofollow" class="external text" href="http://harmful.cat-v.org/cat-v/">UNIX Style, or cat -v Considered Harmful</a> - A paper by Rob Pike on proper Unix command design using cat as an example.</li> <li><a rel="nofollow" class="external text" href="http://man.cat-v.org/unix-1st/1/cat">cat(1) original manual page</a> in the First Edition of <a href="/wiki/Unix" title="Unix">Unix</a>.</li> <li><span class="plainlinksneverexpand"><code><a rel="nofollow" class="external text" href="https://www.gnu.org/software/coreutils/manual/html_node/cat-invocation.html">cat(1)</a></code></span>: concatenate and write files – <a href="/wiki/GNU" title="GNU">GNU</a> <a href="/wiki/Coreutils" class="mw-redirect" title="Coreutils">Coreutils</a> reference</li> <li><span class="plainlinksneverexpand"><code><a rel="nofollow" class="external text" href="https://man.openbsd.org/cat.1">cat(1)</a></code></span>: concatenate and print files – <a href="/wiki/OpenBSD" title="OpenBSD">OpenBSD</a> General Commands <a href="/wiki/Man_page" title="Man page">Manual</a></li> <li><span class="plainlinksneverexpand"><code><a rel="nofollow" class="external text" href="https://www.freebsd.org/cgi/man.cgi?query=cat&sektion=1">cat(1)</a></code></span> – <a href="/wiki/FreeBSD" title="FreeBSD">FreeBSD</a> General Commands <a href="/wiki/Man_page" title="Man page">Manual</a></li> <li><span class="plainlinksneverexpand"><code><a rel="nofollow" class="external text" href="https://9p.io/magic/man2html/1/cat">cat(1)</a></code></span> – <a href="/wiki/Plan_9_from_Bell_Labs" title="Plan 9 from Bell Labs">Plan 9</a> Programmer's Manual, Volume 1</li> <li><span class="plainlinksneverexpand"><code><a rel="nofollow" class="external text" href="https://www.gnu.org/software/coreutils/manual/html_node/tac-invocation.html">tac(1)</a></code></span>: concatenate and write files in reverse – <a href="/wiki/GNU" title="GNU">GNU</a> <a href="/wiki/Coreutils" class="mw-redirect" 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interface">command-line interface</a> programs and <a href="/wiki/Shell_builtin" title="Shell builtin">shell builtins</a></div></th></tr><tr><th scope="row" class="navbox-group" style="width:1%">File system</th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a class="mw-selflink selflink">cat</a></li> <li><a href="/wiki/Chattr" title="Chattr">chattr</a></li> <li><a href="/wiki/Chmod" title="Chmod">chmod</a></li> <li><a href="/wiki/Chown" title="Chown">chown</a></li> <li><a href="/wiki/Chgrp" title="Chgrp">chgrp</a></li> <li><a href="/wiki/Cksum" title="Cksum">cksum</a></li> <li><a href="/wiki/Cmp_(Unix)" title="Cmp (Unix)">cmp</a></li> <li><a href="/wiki/Cp_(Unix)" title="Cp (Unix)">cp</a></li> <li><a href="/wiki/Dd_(Unix)" title="Dd (Unix)">dd</a></li> <li><a href="/wiki/Du_(Unix)" title="Du (Unix)">du</a></li> <li><a href="/wiki/Df_(Unix)" title="Df (Unix)">df</a></li> <li><a href="/wiki/File_(command)" title="File (command)">file</a></li> <li><a href="/wiki/Fuser_(Unix)" title="Fuser (Unix)">fuser</a></li> <li><a href="/wiki/Ln_(Unix)" title="Ln (Unix)">ln</a></li> <li><a href="/wiki/Ls" title="Ls">ls</a></li> <li><a href="/wiki/Mkdir" title="Mkdir">mkdir</a></li> <li><a href="/wiki/Mv_(Unix)" title="Mv (Unix)">mv</a></li> <li><a href="/wiki/Pax_(command)" title="Pax (command)">pax</a></li> <li><a href="/wiki/Pwd" title="Pwd">pwd</a></li> <li><a href="/wiki/Rm_(Unix)" title="Rm (Unix)">rm</a></li> <li><a href="/wiki/Rmdir" title="Rmdir">rmdir</a></li> <li><a href="/wiki/Split_(Unix)" title="Split (Unix)">split</a></li> <li><a href="/wiki/Tee_(command)" title="Tee (command)">tee</a></li> <li><a href="/wiki/Touch_(command)" title="Touch (command)">touch</a></li> <li><a href="/wiki/Type_(Unix)" title="Type (Unix)">type</a></li> <li><a href="/wiki/Umask" title="Umask">umask</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Processes</th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/At_(command)" title="At (command)">at</a></li> <li><a href="/wiki/Job_control_(Unix)#Commands" title="Job control (Unix)">bg</a></li> <li><a href="/wiki/Cron" title="Cron">crontab</a></li> <li><a href="/wiki/Job_control_(Unix)#Commands" title="Job control (Unix)">fg</a></li> <li><a href="/wiki/Kill_(command)" title="Kill (command)">kill</a></li> <li><a href="/wiki/Nice_(Unix)" title="Nice (Unix)">nice</a></li> <li><a href="/wiki/Ps_(Unix)" title="Ps (Unix)">ps</a></li> <li><a href="/wiki/Time_(Unix)" title="Time (Unix)">time</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">User environment</th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Env" title="Env">env</a></li> <li><a href="/wiki/Exit_(command)" title="Exit (command)">exit</a></li> <li><a href="/wiki/Logname" title="Logname">logname</a></li> <li><a href="/wiki/Mesg" title="Mesg">mesg</a></li> <li><a href="/wiki/Talk_(software)" title="Talk (software)">talk</a></li> <li><a href="/wiki/Tput" title="Tput">tput</a></li> <li><a href="/wiki/Uname" title="Uname">uname</a></li> <li><a href="/wiki/Who_(Unix)" title="Who (Unix)">who</a></li> <li><a href="/wiki/Write_(Unix)" title="Write (Unix)">write</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Text processing</th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/AWK" title="AWK">awk</a></li> <li><a href="/wiki/Basename" title="Basename">basename</a></li> <li><a href="/wiki/Comm" title="Comm">comm</a></li> <li><a href="/wiki/Csplit" title="Csplit">csplit</a></li> <li><a href="/wiki/Cut_(Unix)" title="Cut (Unix)">cut</a></li> <li><a href="/wiki/Diff" title="Diff">diff</a></li> <li><a href="/wiki/Dirname" title="Dirname">dirname</a></li> <li><a href="/wiki/Ed_(text_editor)" class="mw-redirect" title="Ed (text editor)">ed</a></li> <li><a href="/wiki/Ex_(text_editor)" title="Ex (text editor)">ex</a></li> <li><a href="/wiki/Fold_(Unix)" title="Fold (Unix)">fold</a></li> <li><a href="/wiki/Head_(Unix)" title="Head (Unix)">head</a></li> <li><a href="/wiki/Iconv" title="Iconv">iconv</a></li> <li><a href="/wiki/Join_(Unix)" title="Join (Unix)">join</a></li> <li><a href="/wiki/M4_(computer_language)" title="M4 (computer language)">m4</a></li> <li><a href="/wiki/More_(command)" title="More (command)">more</a></li> <li><a href="/wiki/Nl_(Unix)" title="Nl (Unix)">nl</a></li> <li><a href="/wiki/Paste_(Unix)" title="Paste (Unix)">paste</a></li> <li><a href="/wiki/Patch_(Unix)" title="Patch (Unix)">patch</a></li> <li><a href="/wiki/Printf_(Unix)" title="Printf (Unix)">printf</a></li> <li><a href="/wiki/Read_(Unix)" title="Read (Unix)">read</a></li> <li><a href="/wiki/Sed" title="Sed">sed</a></li> <li><a href="/wiki/Sort_(Unix)" title="Sort (Unix)">sort</a></li> <li><a href="/wiki/Strings_(Unix)" title="Strings (Unix)">strings</a></li> <li><a href="/wiki/Tail_(Unix)" title="Tail (Unix)">tail</a></li> <li><a href="/wiki/Tr_(Unix)" title="Tr (Unix)">tr</a></li> <li><a href="/wiki/Troff" title="Troff">troff</a></li> <li><a href="/wiki/Uniq" title="Uniq">uniq</a></li> <li><a href="/wiki/Vi_(text_editor)" title="Vi (text editor)">vi</a></li> <li><a href="/wiki/Wc_(Unix)" title="Wc (Unix)">wc</a></li> <li><a href="/wiki/Xargs" title="Xargs">xargs</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Shell_builtin" title="Shell builtin">Shell builtins</a></th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Alias_(command)" title="Alias (command)">alias</a></li> <li><a href="/wiki/Cd_(command)" title="Cd (command)">cd</a></li> <li><a href="/wiki/Echo_(command)" title="Echo (command)">echo</a></li> <li><a href="/wiki/Test_(Unix)" title="Test (Unix)">test</a></li> <li><a href="/wiki/Environment_variable#unset_command" title="Environment variable">unset</a></li> <li><a href="/wiki/Wait_(command)" title="Wait (command)">wait</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Searching</th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Find_(Unix)" title="Find (Unix)">find</a></li> <li><a href="/wiki/Grep" title="Grep">grep</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Documentation</th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Man_page" title="Man page">man</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Software_development" title="Software development">Software development</a></th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Ar_(Unix)" title="Ar (Unix)">ar</a></li> <li><a href="/wiki/Ctags" title="Ctags">ctags</a></li> <li><a href="/wiki/Lex_(software)" title="Lex (software)">lex</a></li> <li><a href="/wiki/Make_(software)" title="Make (software)">make</a></li> <li><a href="/wiki/Nm_(Unix)" title="Nm (Unix)">nm</a></li> <li><a href="/wiki/Strip_(Unix)" title="Strip (Unix)">strip</a></li> <li><a href="/wiki/Yacc" title="Yacc">yacc</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Miscellaneous</th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Bc_(programming_language)" title="Bc (programming language)">bc</a></li> <li><a href="/wiki/Cal_(command)" title="Cal (command)">cal</a></li> <li><a href="/wiki/Expr" title="Expr">expr</a></li> <li><a href="/wiki/System_V_printing_system" title="System V printing system">lp</a></li> <li><a href="/wiki/Od_(Unix)" title="Od (Unix)">od</a></li> <li><a href="/wiki/Sleep_(command)" title="Sleep (command)">sleep</a></li> <li><a href="/wiki/True_and_false_(commands)" title="True and false (commands)">true and false</a></li></ul> </div></td></tr><tr><td class="navbox-abovebelow hlist" colspan="2"><div> <ul><li><span class="noviewer" typeof="mw:File"><span title="Category"><img alt="" src="//upload.wikimedia.org/wikipedia/en/thumb/9/96/Symbol_category_class.svg/16px-Symbol_category_class.svg.png" decoding="async" width="16" height="16" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/9/96/Symbol_category_class.svg/23px-Symbol_category_class.svg.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/9/96/Symbol_category_class.svg/31px-Symbol_category_class.svg.png 2x" data-file-width="180" data-file-height="185" /></span></span> <b>Categories</b> <ul><li><a href="/wiki/Category:Standard_Unix_programs" title="Category:Standard Unix programs">Standard Unix programs</a></li> <li><a href="/wiki/Category:Unix_SUS2008_utilities" title="Category:Unix SUS2008 utilities">Unix SUS2008 utilities</a></li></ul></li> <li><span class="noviewer" typeof="mw:File"><span title="List-Class article"><img alt="" src="//upload.wikimedia.org/wikipedia/en/thumb/d/db/Symbol_list_class.svg/16px-Symbol_list_class.svg.png" decoding="async" width="16" height="16" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/d/db/Symbol_list_class.svg/23px-Symbol_list_class.svg.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/d/db/Symbol_list_class.svg/31px-Symbol_list_class.svg.png 2x" data-file-width="180" data-file-height="185" /></span></span> <b><a href="/wiki/List_of_POSIX_commands" title="List of POSIX commands">List</a></b></li></ul> </div></td></tr></tbody></table></div> <div class="navbox-styles"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236075235"></div><div role="navigation" class="navbox" aria-labelledby="GNU_Core_Utilities_command-line_interface_programs" style="padding:3px"><table class="nowraplinks mw-collapsible autocollapse navbox-inner" style="border-spacing:0;background:transparent;color:inherit"><tbody><tr><th scope="col" class="navbox-title" colspan="2"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1239400231"><div class="navbar plainlinks hlist navbar-mini"><ul><li class="nv-view"><a href="/wiki/Template:Core_Utilities_commands" title="Template:Core Utilities commands"><abbr title="View this template">v</abbr></a></li><li class="nv-talk"><a href="/wiki/Template_talk:Core_Utilities_commands" title="Template talk:Core Utilities commands"><abbr title="Discuss this template">t</abbr></a></li><li class="nv-edit"><a href="/wiki/Special:EditPage/Template:Core_Utilities_commands" title="Special:EditPage/Template:Core Utilities commands"><abbr title="Edit this template">e</abbr></a></li></ul></div><div id="GNU_Core_Utilities_command-line_interface_programs" style="font-size:114%;margin:0 4em"><a href="/wiki/GNU_Core_Utilities" title="GNU Core Utilities">GNU Core Utilities</a> <a href="/wiki/Command-line_interface" title="Command-line interface">command-line interface</a> programs</div></th></tr><tr><th scope="row" class="navbox-group" style="width:1%">File system</th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/w/index.php?title=Chcon&action=edit&redlink=1" class="new" title="Chcon (page does not exist)">chcon</a></li> <li><a href="/wiki/Chmod" title="Chmod">chmod</a></li> <li><a href="/wiki/Chown" title="Chown">chown</a></li> <li><a href="/wiki/Chgrp" title="Chgrp">chgrp</a></li> <li><a href="/wiki/Cksum" title="Cksum">cksum</a></li> <li><a href="/wiki/Cp_(Unix)" title="Cp (Unix)">cp</a></li> <li><a href="/wiki/Dd_(Unix)" title="Dd (Unix)">dd</a></li> <li><a href="/wiki/Df_(Unix)" title="Df (Unix)">df</a></li> <li><a href="/wiki/Ls" title="Ls">dir</a></li> <li><a href="/w/index.php?title=Dircolors_(Unix)&action=edit&redlink=1" class="new" title="Dircolors (Unix) (page does not exist)">dircolors</a></li> <li><a href="/wiki/Install_(Unix)" title="Install (Unix)">install</a></li> <li><a href="/wiki/Ln_(Unix)" title="Ln (Unix)">ln</a></li> <li><a href="/wiki/Ls" title="Ls">ls</a></li> <li><a href="/wiki/Mkdir" title="Mkdir">mkdir</a></li> <li><a href="/wiki/Mkfifo" class="mw-redirect" title="Mkfifo">mkfifo</a></li> <li><a href="/wiki/Mknod" class="mw-redirect" title="Mknod">mknod</a></li> <li><a href="/wiki/Mktemp" title="Mktemp">mktemp</a></li> <li><a href="/wiki/Mv_(Unix)" title="Mv (Unix)">mv</a></li> <li><a href="/w/index.php?title=Realpath&action=edit&redlink=1" class="new" title="Realpath (page does not exist)">realpath</a></li> <li><a href="/wiki/Rm_(Unix)" title="Rm (Unix)">rm</a></li> <li><a href="/wiki/Rmdir" title="Rmdir">rmdir</a></li> <li><a href="/wiki/Shred_(Unix)" title="Shred (Unix)">shred</a></li> <li><a href="/wiki/Sync_(Unix)" title="Sync (Unix)">sync</a></li> <li><a href="/wiki/Touch_(command)" title="Touch (command)">touch</a></li> <li><a href="/wiki/Truncate" class="mw-redirect" title="Truncate">truncate</a></li> <li><a href="/wiki/Ls" title="Ls">vdir</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Text utilities</th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/w/index.php?title=B2sum&action=edit&redlink=1" class="new" title="B2sum (page does not exist)">b2sum</a></li> <li><a href="/wiki/Base32" title="Base32">base32</a></li> <li><a href="/wiki/Base64" title="Base64">base64</a></li> <li><a class="mw-selflink selflink">cat</a></li> <li><a href="/wiki/Cksum" title="Cksum">cksum</a></li> <li><a href="/wiki/Comm" title="Comm">comm</a></li> <li><a href="/wiki/Csplit" title="Csplit">csplit</a></li> <li><a href="/wiki/Cut_(Unix)" title="Cut (Unix)">cut</a></li> <li><a href="/wiki/Expand_(Unix)" title="Expand (Unix)">expand</a></li> <li><a href="/wiki/Fmt_(Unix)" title="Fmt (Unix)">fmt</a></li> <li><a href="/wiki/Fold_(Unix)" title="Fold (Unix)">fold</a></li> <li><a href="/wiki/Head_(Unix)" title="Head (Unix)">head</a></li> <li><a href="/wiki/Join_(Unix)" title="Join (Unix)">join</a></li> <li><a href="/wiki/Md5sum" title="Md5sum">md5sum</a></li> <li><a href="/wiki/Nl_(Unix)" title="Nl (Unix)">nl</a></li> <li><a href="/w/index.php?title=Numfmt&action=edit&redlink=1" class="new" title="Numfmt (page does not exist)">numfmt</a></li> <li><a href="/wiki/Od_(Unix)" title="Od (Unix)">od</a></li> <li><a href="/wiki/Paste_(Unix)" title="Paste (Unix)">paste</a></li> <li><a href="/wiki/Ptx_(Unix)" title="Ptx (Unix)">ptx</a></li> <li><a href="/wiki/Pr_(Unix)" title="Pr (Unix)">pr</a></li> <li><a href="/wiki/Sha1sum" title="Sha1sum">sha1sum</a></li> <li><a href="/wiki/Shuf" title="Shuf">shuf</a></li> <li><a href="/wiki/Sort_(Unix)" title="Sort (Unix)">sort</a></li> <li><a href="/wiki/Split_(Unix)" title="Split (Unix)">split</a></li> <li><a href="/wiki/Sum_(Unix)" title="Sum (Unix)">sum</a></li> <li>tac</li> <li><a href="/wiki/Tail_(Unix)" title="Tail (Unix)">tail</a></li> <li><a href="/wiki/Tr_(Unix)" title="Tr (Unix)">tr</a></li> <li><a href="/wiki/Tsort" title="Tsort">tsort</a></li> <li><a href="/wiki/Unexpand" title="Unexpand">unexpand</a></li> <li><a href="/wiki/Uniq" title="Uniq">uniq</a></li> <li><a href="/wiki/Wc_(Unix)" title="Wc (Unix)">wc</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Shell utilities</th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Uname" title="Uname">arch</a></li> <li><a href="/wiki/Basename" title="Basename">basename</a></li> <li><a href="/wiki/Chroot" title="Chroot">chroot</a></li> <li><a href="/wiki/Unix_time#Command_line" title="Unix time">date</a></li> <li><a href="/wiki/Dirname" title="Dirname">dirname</a></li> <li><a href="/wiki/Du_(Unix)" title="Du (Unix)">du</a></li> <li><a href="/wiki/Echo_(command)" title="Echo (command)">echo</a></li> <li><a href="/wiki/Env" title="Env">env</a></li> <li><a href="/wiki/Expr" title="Expr">expr</a></li> <li><a href="/wiki/Factor_(Unix)" title="Factor (Unix)">factor</a></li> <li><a href="/wiki/True_and_false_(commands)" title="True and false (commands)">false</a></li> <li><a href="/wiki/Groups_(Unix)" class="mw-redirect" title="Groups (Unix)">groups</a></li> <li><a href="/w/index.php?title=Hostid_(Unix)&action=edit&redlink=1" class="new" title="Hostid (Unix) (page does not exist)">hostid</a></li> <li><a href="/wiki/Id_(Unix)" class="mw-redirect" title="Id (Unix)">id</a></li> <li><a href="/wiki/Link_(Unix)" title="Link (Unix)">link</a></li> <li><a href="/wiki/Logname" title="Logname">logname</a></li> <li><a href="/wiki/Nice_(Unix)" title="Nice (Unix)">nice</a></li> <li><a href="/wiki/Nohup" title="Nohup">nohup</a></li> <li><a href="/w/index.php?title=Nproc&action=edit&redlink=1" class="new" title="Nproc (page does not exist)">nproc</a></li> <li><a href="/w/index.php?title=Pathchk_(Unix)&action=edit&redlink=1" class="new" title="Pathchk (Unix) (page does not exist)">pathchk</a></li> <li><a href="/w/index.php?title=Pinky_(Unix)&action=edit&redlink=1" class="new" title="Pinky (Unix) (page does not exist)">pinky</a></li> <li><a href="/wiki/Printenv" class="mw-redirect" title="Printenv">printenv</a></li> <li><a href="/wiki/Printf" title="Printf">printf</a></li> <li><a href="/wiki/Pwd" title="Pwd">pwd</a></li> <li><a href="/wiki/Readlink" class="mw-redirect" title="Readlink">readlink</a></li> <li><a href="/w/index.php?title=Runcon&action=edit&redlink=1" class="new" title="Runcon (page does not exist)">runcon</a></li> <li><a href="/wiki/Seq_(Unix)" title="Seq (Unix)">seq</a></li> <li><a href="/wiki/Sleep_(command)" title="Sleep (command)">sleep</a></li> <li>stat</li> <li><a href="/w/index.php?title=Stdbuf&action=edit&redlink=1" class="new" title="Stdbuf (page does not exist)">stdbuf</a></li> <li><a href="/wiki/Stty_(Unix)" class="mw-redirect" title="Stty (Unix)">stty</a></li> <li><a href="/wiki/Tee_(command)" title="Tee (command)">tee</a></li> <li><a href="/wiki/Test_(Unix)" title="Test (Unix)">test</a></li> <li><a href="/wiki/Timeout_(computing)" title="Timeout (computing)">timeout</a></li> <li><a href="/wiki/True_and_false_(commands)" title="True and false (commands)">true</a></li> <li><a href="/wiki/Tty_(Unix)" title="Tty (Unix)">tty</a></li> <li><a href="/wiki/Uname" title="Uname">uname</a></li> <li><a href="/wiki/Unlink_(Unix)" title="Unlink (Unix)">unlink</a></li> <li><a href="/wiki/Uptime#coreutils" title="Uptime">uptime</a></li> <li><a href="/wiki/Users_(Unix)" class="mw-redirect" title="Users (Unix)">users</a></li> <li><a href="/wiki/Who_(Unix)" title="Who (Unix)">who</a></li> <li><a href="/wiki/Whoami" title="Whoami">whoami</a></li> <li><a href="/wiki/Yes_(Unix)" title="Yes (Unix)">yes</a></li></ul> </div></td></tr></tbody></table></div>    </div><noscript><img src="https://login.wikimedia.org/wiki/Special:CentralAutoLogin/start?type=1x1" alt="" width="1" height="1" style="border: none; position: absolute;"></noscript> <div class="printfooter" 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