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class="vector-toc-list"> </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">5</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">6</span> <span>References</span> </div> </a> <ul id="toc-References-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 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href="https://es.wikipedia.org/wiki/Identificador_de_grupo" title="Identificador de grupo – Spanish" lang="es" hreflang="es" data-title="Identificador de grupo" data-language-autonym="Español" data-language-local-name="Spanish" class="interlanguage-link-target"><span>Español</span></a></li><li class="interlanguage-link interwiki-fr mw-list-item"><a href="https://fr.wikipedia.org/wiki/Groupe_(Unix)" title="Groupe (Unix) – French" lang="fr" hreflang="fr" data-title="Groupe (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/%EA%B7%B8%EB%A3%B9_%EC%8B%9D%EB%B3%84%EC%9E%90" title="그룹 식별자 – Korean" lang="ko" hreflang="ko" data-title="그룹 식별자" data-language-autonym="한국어" data-language-local-name="Korean" class="interlanguage-link-target"><span>한국어</span></a></li><li class="interlanguage-link interwiki-it mw-list-item"><a href="https://it.wikipedia.org/wiki/Group_identifier" title="Group identifier – Italian" lang="it" hreflang="it" data-title="Group identifier" data-language-autonym="Italiano" data-language-local-name="Italian" class="interlanguage-link-target"><span>Italiano</span></a></li><li class="interlanguage-link interwiki-ja badge-Q70894304 mw-list-item" title=""><a href="https://ja.wikipedia.org/wiki/%E3%82%B0%E3%83%AB%E3%83%BC%E3%83%97%E8%AD%98%E5%88%A5%E5%AD%90" title="グループ識別子 – Japanese" lang="ja" hreflang="ja" data-title="グループ識別子" 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-no mw-list-item"><a href="https://no.wikipedia.org/wiki/Gruppeidentifikator" title="Gruppeidentifikator – Norwegian Bokmål" lang="nb" hreflang="nb" data-title="Gruppeidentifikator" data-language-autonym="Norsk bokmål" data-language-local-name="Norwegian Bokmål" class="interlanguage-link-target"><span>Norsk bokmål</span></a></li><li class="interlanguage-link interwiki-pl mw-list-item"><a href="https://pl.wikipedia.org/wiki/GID" title="GID – Polish" lang="pl" hreflang="pl" data-title="GID" data-language-autonym="Polski" data-language-local-name="Polish" class="interlanguage-link-target"><span>Polski</span></a></li><li class="interlanguage-link interwiki-uk mw-list-item"><a href="https://uk.wikipedia.org/wiki/%D0%86%D0%B4%D0%B5%D0%BD%D1%82%D0%B8%D1%84%D1%96%D0%BA%D0%B0%D1%82%D0%BE%D1%80_%D0%B3%D1%80%D1%83%D0%BF%D0%B8" title="Ідентифікатор групи – Ukrainian" lang="uk" hreflang="uk" data-title="Ідентифікатор групи" data-language-autonym="Українська" data-language-local-name="Ukrainian" class="interlanguage-link-target"><span>Українська</span></a></li><li class="interlanguage-link interwiki-zh mw-list-item"><a href="https://zh.wikipedia.org/wiki/%E7%BB%84ID" title="组ID – Chinese" lang="zh" hreflang="zh" data-title="组ID" data-language-autonym="中文" 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data-unpinned-container-id="vector-appearance-unpinned-container" > <div class="vector-pinnable-header-label">Appearance</div> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-pin-button" data-event-name="pinnable-header.vector-appearance.pin">move to sidebar</button> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-unpin-button" data-event-name="pinnable-header.vector-appearance.unpin">hide</button> </div> </div> </div> </nav> </div> </div> <div id="bodyContent" class="vector-body" aria-labelledby="firstHeading" data-mw-ve-target-container> <div class="vector-body-before-content"> <div class="mw-indicators"> </div> <div id="siteSub" class="noprint">From Wikipedia, the free encyclopedia</div> </div> <div id="contentSub"><div id="mw-content-subtitle"><span class="mw-redirectedfrom">(Redirected from <a href="/w/index.php?title=Group_identifier_(Unix)&redirect=no" class="mw-redirect" title="Group identifier (Unix)">Group identifier (Unix)</a>)</span></div></div> <div id="mw-content-text" class="mw-body-content"><div class="mw-content-ltr mw-parser-output" lang="en" dir="ltr"><div class="shortdescription nomobile noexcerpt noprint searchaux" style="display:none">Unix/POSIX system account group number; numeric value used to represent a specific group</div> <style data-mw-deduplicate="TemplateStyles:r1236090951">.mw-parser-output .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">"Egid" redirects here. For the Egyptian General Intelligence Directorate, see <a href="/wiki/Egyptian_General_Intelligence_Directorate" class="mw-redirect" title="Egyptian General Intelligence Directorate">Egyptian General Intelligence Directorate</a>.</div> <style data-mw-deduplicate="TemplateStyles:r1251242444">.mw-parser-output .ambox{border:1px solid #a2a9b1;border-left:10px solid #36c;background-color:#fbfbfb;box-sizing:border-box}.mw-parser-output .ambox+link+.ambox,.mw-parser-output .ambox+link+style+.ambox,.mw-parser-output .ambox+link+link+.ambox,.mw-parser-output .ambox+.mw-empty-elt+link+.ambox,.mw-parser-output .ambox+.mw-empty-elt+link+style+.ambox,.mw-parser-output .ambox+.mw-empty-elt+link+link+.ambox{margin-top:-1px}html body.mediawiki .mw-parser-output .ambox.mbox-small-left{margin:4px 1em 4px 0;overflow:hidden;width:238px;border-collapse:collapse;font-size:88%;line-height:1.25em}.mw-parser-output .ambox-speedy{border-left:10px solid #b32424;background-color:#fee7e6}.mw-parser-output .ambox-delete{border-left:10px solid #b32424}.mw-parser-output .ambox-content{border-left:10px solid #f28500}.mw-parser-output .ambox-style{border-left:10px solid #fc3}.mw-parser-output .ambox-move{border-left:10px solid #9932cc}.mw-parser-output .ambox-protection{border-left:10px solid #a2a9b1}.mw-parser-output .ambox .mbox-text{border:none;padding:0.25em 0.5em;width:100%}.mw-parser-output .ambox .mbox-image{border:none;padding:2px 0 2px 0.5em;text-align:center}.mw-parser-output .ambox .mbox-imageright{border:none;padding:2px 0.5em 2px 0;text-align:center}.mw-parser-output .ambox .mbox-empty-cell{border:none;padding:0;width:1px}.mw-parser-output .ambox .mbox-image-div{width:52px}@media(min-width:720px){.mw-parser-output .ambox{margin:0 10%}}@media print{body.ns-0 .mw-parser-output .ambox{display:none!important}}</style><table class="box-More_citations_needed plainlinks metadata ambox ambox-content ambox-Refimprove" role="presentation"><tbody><tr><td class="mbox-image"><div class="mbox-image-div"><span typeof="mw:File"><a href="/wiki/File:Question_book-new.svg" class="mw-file-description"><img alt="" src="//upload.wikimedia.org/wikipedia/en/thumb/9/99/Question_book-new.svg/50px-Question_book-new.svg.png" decoding="async" width="50" height="39" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/9/99/Question_book-new.svg/75px-Question_book-new.svg.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/9/99/Question_book-new.svg/100px-Question_book-new.svg.png 2x" data-file-width="512" data-file-height="399" /></a></span></div></td><td class="mbox-text"><div class="mbox-text-span">This article <b>needs additional citations for <a href="/wiki/Wikipedia:Verifiability" title="Wikipedia:Verifiability">verification</a></b>.<span class="hide-when-compact"> Please help <a href="/wiki/Special:EditPage/Group_identifier" title="Special:EditPage/Group identifier">improve this article</a> by <a href="/wiki/Help:Referencing_for_beginners" title="Help:Referencing for beginners">adding citations to reliable sources</a>. Unsourced material may be challenged and removed.<br /><small><span class="plainlinks"><i>Find sources:</i> <a rel="nofollow" class="external text" href="https://www.google.com/search?as_eq=wikipedia&q=%22Group+identifier%22">"Group identifier"</a> – <a rel="nofollow" class="external text" href="https://www.google.com/search?tbm=nws&q=%22Group+identifier%22+-wikipedia&tbs=ar:1">news</a> <b>·</b> <a rel="nofollow" class="external text" href="https://www.google.com/search?&q=%22Group+identifier%22&tbs=bkt:s&tbm=bks">newspapers</a> <b>·</b> <a rel="nofollow" class="external text" href="https://www.google.com/search?tbs=bks:1&q=%22Group+identifier%22+-wikipedia">books</a> <b>·</b> <a rel="nofollow" class="external text" href="https://scholar.google.com/scholar?q=%22Group+identifier%22">scholar</a> <b>·</b> <a rel="nofollow" class="external text" href="https://www.jstor.org/action/doBasicSearch?Query=%22Group+identifier%22&acc=on&wc=on">JSTOR</a></span></small></span> <span class="date-container"><i>(<span class="date">September 2014</span>)</i></span><span class="hide-when-compact"><i> (<small><a href="/wiki/Help:Maintenance_template_removal" title="Help:Maintenance template removal">Learn how and when to remove this message</a></small>)</i></span></div></td></tr></tbody></table> <p>In <a href="/wiki/Unix-like" title="Unix-like">Unix-like</a> systems, multiple users can be put into <i><a href="/wiki/Group_(computing)" title="Group (computing)">groups</a></i>. <a href="/wiki/POSIX" title="POSIX">POSIX</a> and conventional <a href="/wiki/Unix" title="Unix">Unix</a> <a href="/wiki/File_system_permissions" class="mw-redirect" title="File system permissions">file system permissions</a> are organized into three classes, <i>user</i>, <i>group</i>, and <i>others</i>. The use of groups allows additional abilities to be delegated in an organized fashion, such as access to disks, <a href="/wiki/Computer_printer" class="mw-redirect" title="Computer printer">printers</a>, and other <a href="/wiki/Peripheral" title="Peripheral">peripherals</a>. This method, among others, also enables the <a href="/wiki/Superuser" title="Superuser">superuser</a> to delegate some administrative tasks to normal users, similar to the <i>Administrators</i> group on <a href="/wiki/Windows_NT" title="Windows NT">Microsoft Windows NT</a> and its derivatives. </p><p>A <b>group identifier</b>, often abbreviated to <b>GID</b>, is a numeric value used to represent a specific group.<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> The range of values for a GID varies amongst different systems; at the very least, a GID can be between 0 and 32,767, with one restriction: the login group for the superuser must have GID 0. This numeric value is used to refer to groups in the <code><a href="/wiki//etc/passwd" class="mw-redirect" title="/etc/passwd">/etc/passwd</a></code> and <code>/etc/group</code> files or their equivalents. <a href="/wiki/Shadow_passwords" class="mw-redirect" title="Shadow passwords">Shadow password</a> files and <a href="/wiki/Network_Information_Service" title="Network Information Service">Network Information Service</a> also refer to numeric GIDs. The group identifier is a necessary component of <a href="/wiki/Unix" title="Unix">Unix</a> <a href="/wiki/File_system" title="File system">file systems</a> and <a href="/wiki/Process_(computing)" title="Process (computing)">processes</a>. </p> <meta property="mw:PageProp/toc" /> <div class="mw-heading mw-heading2"><h2 id="Supplementary_groups">Supplementary groups</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Group_identifier&action=edit&section=1" title="Edit section: Supplementary groups"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>In Unix systems, every user must be a member of at least one group, the <b>primary group</b>, which is identified by the numeric GID of the user's entry in the passwd database, which can be viewed with the command <code>getent passwd</code> (usually stored in <code>/etc/passwd</code> or <a href="/wiki/LDAP" class="mw-redirect" title="LDAP">LDAP</a>). This group is referred to as the <i>primary group ID</i>. A user may be listed as member of additional groups in the relevant entries in the group database, which can be viewed with <code>getent group</code> (usually stored in <code>/etc/group</code> or <a href="/wiki/LDAP" class="mw-redirect" title="LDAP">LDAP</a>); the IDs of these groups are referred to as <i>supplementary group IDs</i>. </p> <div class="mw-heading mw-heading2"><h2 id="Effective_vs._real">Effective vs. real</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Group_identifier&action=edit&section=2" title="Edit section: Effective vs. real"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Unix processes have an <a href="/wiki/Effective_user_ID" class="mw-redirect" title="Effective user ID">effective</a> (EUID, EGID), a <a href="/wiki/Real_user_ID" class="mw-redirect" title="Real user ID">real</a> (UID, GID) and a <a href="/wiki/Saved_user_ID" class="mw-redirect" title="Saved user ID">saved</a> (SUID, SGID) ID. Normally these are identical, but in <code><a href="/wiki/Setuid" title="Setuid">setuid</a></code> and <code><a href="/wiki/Setgid" class="mw-redirect" title="Setgid">setgid</a></code> processes they are different. </p> <div class="mw-heading mw-heading2"><h2 id="Conventions">Conventions</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Group_identifier&action=edit&section=3" title="Edit section: Conventions"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <div class="mw-heading mw-heading3"><h3 id="Type">Type</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Group_identifier&action=edit&section=4" title="Edit section: Type"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Originally, a signed 16-bit integer was used. Since the sign was not necessary – negative numbers do not make valid group IDs – an unsigned integer is now used instead, allowing group IDs between 0 and 65,535. Modern operating systems usually use unsigned 32-bit integers, which allow for group IDs between 0 and 4,294,967,295. </p> <div class="mw-heading mw-heading3"><h3 id="Reserved_ranges">Reserved ranges</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Group_identifier&action=edit&section=5" title="Edit section: Reserved ranges"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Many Linux systems reserve the GID number range 0 to 99 for statically allocated groups, and either 100−499 or 100−999 for groups dynamically allocated by the system in post-installation scripts. These ranges are often specified in <code>/etc/login.defs</code>, for <code>useradd</code>, <code>groupadd</code> and similar tools. </p><p>On FreeBSD, porters who need a GID for their package can pick a free one from the range 50 to 999 and then register this static allocation in <a rel="nofollow" class="external text" href="http://svnweb.freebsd.org/ports/head/GIDs?view=co">ports/GIDs</a>.<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> </p> <div class="mw-heading mw-heading3"><h3 id="Special_values">Special values</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Group_identifier&action=edit&section=6" title="Edit section: Special values"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li>0: The <a href="/wiki/Superuser" title="Superuser">superuser</a> normally has a GID of zero (0).</li> <li>−1: The value <code>(gid_t) -1</code> is reserved by POSIX to identify an omitted argument.<sup id="cite_ref-3" class="reference"><a href="#cite_note-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup></li> <li>65,534: The Linux kernel defaults to 2<sup>16</sup>−2 = 65,534 (which many Linux distributions map to the group name "nogroup") when a 32-bit GID does not fit into the return value of a 16-bit system call.<sup id="cite_ref-4" class="reference"><a href="#cite_note-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup> The value is also returned by <a href="/w/index.php?title=Idmapd&action=edit&redlink=1" class="new" title="Idmapd (page does not exist)">idmapd</a> if a group name in an incoming <a href="/wiki/NFSv4" class="mw-redirect" title="NFSv4">NFSv4</a> packet does not match any known group on the system.</li></ul> <div class="mw-heading mw-heading2"><h2 id="Personal_groups">Personal groups</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Group_identifier&action=edit&section=7" title="Edit section: Personal groups"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Many system administrators allocate for each user also a personal primary group that has the same name as the user's login name, and often also has the same numeric GID as the user's UID. Such personal groups have no other members and make collaboration with other users in shared directories easier, by allowing users to habitually work with <code><a href="/wiki/Umask" title="Umask">umask</a> 0002</code>. This way, newly created files can have by default write permissions enabled for group members, because this will normally only enable write access for members of the personal group, that is only for the file's owner. However, if a file is created in a shared directory that belongs to another group and has the <a href="/wiki/Setgid" class="mw-redirect" title="Setgid">setgid</a> bit set, then the created file will automatically become writable to members of that directory's group as well. </p><p>On many Linux systems, the <code>USERGROUPS_ENAB</code> variable in <code>/etc/login.defs</code> controls whether commands like <code>useradd</code> or <code>userdel</code> automatically add or delete an associated personal group. </p> <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=Group_identifier&action=edit&section=8" title="Edit section: See also"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><a href="/wiki/Setuid" title="Setuid">setuid</a></li> <li><a href="/wiki/User_identifier" title="User identifier">User identifier</a></li> <li><a href="/wiki/Process_identifier" title="Process identifier">Process identifier</a></li> <li><a href="/wiki/Inode" title="Inode">Inode</a></li> <li><a href="/wiki/FAT_access_rights" class="mw-redirect" title="FAT access rights">FAT access rights</a></li> <li><a href="/wiki/List_of_POSIX_commands" title="List of POSIX commands">List of POSIX commands</a></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=Group_identifier&action=edit&section=9" title="Edit section: References"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <div class="mw-references-wrap"><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://pubs.opengroup.org/onlinepubs/9699919799.2018edition/basedefs/V1_chap03.html">"Definitions"</a>. <i>pubs.opengroup.org</i><span class="reference-accessdate">. Retrieved <span class="nowrap">2021-12-06</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=pubs.opengroup.org&rft.atitle=Definitions&rft_id=https%3A%2F%2Fpubs.opengroup.org%2Fonlinepubs%2F9699919799.2018edition%2Fbasedefs%2FV1_chap03.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AGroup+identifier" 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"><a rel="nofollow" class="external text" href="http://www.freebsd.org/doc/en/books/porters-handbook/">FreeBSD Porter's Handbook</a>, <a rel="nofollow" class="external text" href="http://www.freebsd.org/doc/en/books/porters-handbook/users-and-groups.html">Section 6.26: Adding Users and Groups</a></span> </li> <li id="cite_note-3"><span class="mw-cite-backlink"><b><a href="#cite_ref-3">^</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://pubs.opengroup.org/onlinepubs/009695399/functions/chown.html">"chown"</a>. <i>pubs.opengroup.org</i><span class="reference-accessdate">. Retrieved <span class="nowrap">2021-12-06</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=pubs.opengroup.org&rft.atitle=chown&rft_id=https%3A%2F%2Fpubs.opengroup.org%2Fonlinepubs%2F009695399%2Ffunctions%2Fchown.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AGroup+identifier" class="Z3988"></span></span> </li> <li id="cite_note-4"><span class="mw-cite-backlink"><b><a href="#cite_ref-4">^</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://lwn.net/Articles/532593/">"Namespaces in operation, part 5: User namespaces [LWN.net]"</a>. <i>lwn.net</i><span class="reference-accessdate">. Retrieved <span class="nowrap">2021-12-06</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=lwn.net&rft.atitle=Namespaces+in+operation%2C+part+5%3A+User+namespaces+%5BLWN.net%5D&rft_id=https%3A%2F%2Flwn.net%2FArticles%2F532593%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3AGroup+identifier" class="Z3988"></span></span> </li> </ol></div>    </div><noscript><img src="https://login.wikimedia.org/wiki/Special:CentralAutoLogin/start?useformat=desktop&type=1x1&usesul3=0" alt="" width="1" height="1" style="border: none; position: absolute;"></noscript> <div class="printfooter" data-nosnippet="">Retrieved from "<a dir="ltr" href="https://en.wikipedia.org/w/index.php?title=Group_identifier&oldid=1252033931">https://en.wikipedia.org/w/index.php?title=Group_identifier&oldid=1252033931</a>"</div></div> <div id="catlinks" class="catlinks" data-mw="interface"><div id="mw-normal-catlinks" class="mw-normal-catlinks"><a href="/wiki/Help:Category" title="Help:Category">Categories</a>: <ul><li><a href="/wiki/Category:Unix" title="Category:Unix">Unix</a></li><li><a href="/wiki/Category:Unix_file_system_technology" title="Category:Unix file system technology">Unix file system technology</a></li></ul></div><div id="mw-hidden-catlinks" class="mw-hidden-catlinks mw-hidden-cats-hidden">Hidden categories: <ul><li><a href="/wiki/Category:Articles_with_short_description" title="Category:Articles with short description">Articles with short description</a></li><li><a href="/wiki/Category:Short_description_matches_Wikidata" title="Category:Short description matches Wikidata">Short description matches Wikidata</a></li><li><a href="/wiki/Category:Articles_needing_additional_references_from_September_2014" title="Category:Articles needing additional references from September 2014">Articles needing additional references from September 2014</a></li><li><a href="/wiki/Category:All_articles_needing_additional_references" title="Category:All articles needing additional references">All articles needing additional references</a></li></ul></div></div> </div> </main> </div> <div class="mw-footer-container"> <footer id="footer" class="mw-footer" > <ul id="footer-info"> <li id="footer-info-lastmod"> This page was last edited on 19 October 2024, at 12:27<span class="anonymous-show"> (UTC)</span>.</li> <li id="footer-info-copyright">Text is available under the <a href="/wiki/Wikipedia:Text_of_the_Creative_Commons_Attribution-ShareAlike_4.0_International_License" title="Wikipedia:Text of the Creative Commons Attribution-ShareAlike 4.0 International License">Creative Commons Attribution-ShareAlike 4.0 License</a>; additional terms may apply. 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