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List of POSIX commands
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<h2 id="list">List</h2> IEEE Std 1003.1-2024 utilities<table><tbody><tr><th scope="col">Name</th><th scope="col">Category</th><th scope="col">Status (Option code)</th><th scope="col">Description</th><th scope="col">First appeared</th></tr><tr><th scope="row">admin</th><td><a href="/facts/Source_Code_Control_System/v85GIeBx">SCCS</a></td><td>Optional (XSI)</td><td>Create and administer <a href="/facts/Source_Code_Control_System/v85GIeBx">SCCS</a> files</td><td>PWB UNIX</td></tr><tr><th scope="row"><a href="/facts/Alias_(command)/BL5hJMxl">alias</a></th><td>Misc</td><td>Mandatory</td><td>Define or display aliases</td><td></td></tr><tr><th scope="row"><a href="/facts/Ar_(Unix)/1MUuS0pp">ar</a></th><td>Misc</td><td>Mandatory</td><td>Create and maintain <a href="/facts/Library_(computing)/xRzL3P7q">library</a> archives</td><td>Version 1 AT&T UNIX</td></tr><tr><th scope="row"><a href="/facts/Asa_(Unix)/EEuIsUx9">asa</a></th><td>Text processing</td><td>Optional (FR)</td><td>Interpret <a href="/facts/ASA_carriage_control_characters/BxVIrW1G">carriage-control</a> characters</td><td>System V</td></tr><tr><th scope="row"><a href="/facts/At_(command)/DRx3Fyav">at</a></th><td>Process management</td><td>Mandatory</td><td>Execute commands at a later time</td><td>Version 7 AT&T UNIX</td></tr><tr><th scope="row"><a href="/facts/AWK/lAQ0leyj">awk</a></th><td>Text processing</td><td>Mandatory</td><td>Pattern scanning and processing language</td><td>Version 7 AT&T UNIX</td></tr><tr><th scope="row"><a href="/facts/Basename/EwoA4aB3">basename</a></th><td>Filesystem</td><td>Mandatory</td><td>Return non-directory portion of a pathname; see also dirname</td><td>Version 7 AT&T UNIX</td></tr><tr><th scope="row"><a href="/facts/Batch_(Unix)/DRx3Fyav">batch</a></th><td>Process management</td><td>Mandatory</td><td>Schedule commands to be executed in a batch queue</td><td></td></tr><tr><th scope="row"><a href="/facts/Bc_(programming_language)/8nUNyNeD">bc</a></th><td>Misc</td><td>Mandatory</td><td><a href="/facts/Arbitrary-precision_arithmetic/cXxc8yB2">Arbitrary-precision arithmetic</a> language</td><td>Version 6 AT&T UNIX</td></tr><tr><th scope="row"><a href="/facts/Bg_(Unix)/NIzeWzjq">bg</a></th><td>Process management</td><td>Optional (UP)</td><td>Run jobs in the background</td><td></td></tr><tr><th scope="row"><a href="/facts/C_compiler/cPL7x9ld">cc</a>/<a href="/facts/C17_(C_standard_revision)/NGAWJzq6">c17</a></th><td>C programming</td><td>Optional (CD)</td><td><a href="/facts/Compiler/WNfCDFJe">Compile</a> standard <a href="/facts/C_(programming_language)/Ky2No763">C</a> programs</td><td>IEEE Std 1003.1-2024</td></tr><tr><th scope="row"><a href="/facts/Cal_(command)/FplhbrQY">cal</a></th><td>Misc</td><td>Optional (XSI)</td><td>Print a calendar</td><td>Version 5 AT&T UNIX</td></tr><tr><th scope="row"><a href="/facts/Cat_(Unix)/KQPATH6w">cat</a></th><td>Filesystem</td><td>Mandatory</td><td>Concatenate and print files</td><td>PDP-7 UNIX</td></tr><tr><th scope="row"><a href="/facts/Cd_(command)/GRT0BkeF">cd</a></th><td>Filesystem</td><td>Mandatory</td><td>Change the working directory</td><td>Version 6 AT&T UNIX</td></tr><tr><th scope="row"><a href="/facts/Cflow/7JefaA3B">cflow</a></th><td>C programming</td><td>Optional (XSI)</td><td>Generate a C-language <a href="/facts/Call_graph/Uk0b0mdN">call graph</a></td><td>System V</td></tr><tr><th scope="row"><a href="/facts/Chgrp/L1sDNa1r">chgrp</a></th><td>Filesystem</td><td>Mandatory</td><td>Change the file group ownership</td><td>PWB UNIX</td></tr><tr><th scope="row"><a href="/facts/Chmod/aGRdWvvk">chmod</a></th><td>Filesystem</td><td>Mandatory</td><td>Change the file modes/attributes/permissions</td><td>PDP-7 UNIX</td></tr><tr><th scope="row"><a href="/facts/Chown/JPm7Xv6u">chown</a></th><td>Filesystem</td><td>Mandatory</td><td>Change the file ownership</td><td>PDP-7 UNIX</td></tr><tr><th scope="row"><a href="/facts/Cksum/gQe72GRy">cksum</a></th><td>Filesystem</td><td>Mandatory</td><td>Write file <a href="/facts/Checksum/AqxQ0I8g">checksums</a> and sizes</td><td>4.4BSD</td></tr><tr><th scope="row"><a href="/facts/Cmp_(Unix)/EGTTz5A8">cmp</a></th><td>Filesystem</td><td>Mandatory</td><td>Compare two files; see also diff</td><td>Version 1 AT&T UNIX</td></tr><tr><th scope="row"><a href="/facts/Comm/NvuxhDwE">comm</a></th><td>Text processing</td><td>Mandatory</td><td>Select or reject lines common to two files</td><td>Version 4 AT&T UNIX</td></tr><tr><th scope="row"><a href="/facts/Command_(Unix)/3HN53Hz1">command</a></th><td>Shell programming</td><td>Mandatory</td><td>Execute a simple command</td><td></td></tr><tr><th scope="row"><a href="/facts/Compress/RLSgGNUX">compress</a></th><td>Filesystem</td><td>Optional (XSI)</td><td>Compress data</td><td>4.3BSD</td></tr><tr><th scope="row"><a href="/facts/Cp_(Unix)/T7n2B1Fg">cp</a></th><td>Filesystem</td><td>Mandatory</td><td>Copy files</td><td>PDP-7 UNIX</td></tr><tr><th scope="row"><a href="/facts/Crontab/y2tTGCQI">crontab</a></th><td>Misc</td><td>Mandatory</td><td>Schedule periodic background work</td><td>System V</td></tr><tr><th scope="row"><a href="/facts/Csplit/B2Em6ogs">csplit</a></th><td>Text processing</td><td>Mandatory</td><td>Split files based on context</td><td>PWB UNIX</td></tr><tr><th scope="row"><a href="/facts/Ctags/pxQedaX0">ctags</a></th><td>C programming</td><td>Optional (SD)</td><td>Create a tags file</td><td>3BSD</td></tr><tr><th scope="row"><a href="/facts/Cut_(Unix)/M9qXNlAB">cut</a></th><td>Text processing</td><td>Mandatory</td><td>Cut out selected fields of each line of a file</td><td>System III</td></tr><tr><th scope="row"><a href="/facts/Cxref/EEuIsUx9">cxref</a></th><td>C programming</td><td>Optional (XSI)</td><td>Generate a <a href="/facts/C_(programming_language)/Ky2No763">C-language</a> program cross-reference table</td><td>System V</td></tr><tr><th scope="row">date</th><td>Misc</td><td>Mandatory</td><td>Sets or displays the date and time</td><td>Version 1 AT&T UNIX</td></tr><tr><th scope="row"><a href="/facts/Dd_(Unix)/Ksttbob5">dd</a></th><td>Filesystem</td><td>Mandatory</td><td>Convert and copy a file</td><td>Version 5 AT&T UNIX</td></tr><tr><th scope="row"><a href="/facts/Delta_(Unix)/EEuIsUx9">delta</a></th><td>SCCS</td><td>Optional (XSI)</td><td>Make a delta (change) to an SCCS file</td><td>PWB UNIX</td></tr><tr><th scope="row"><a href="/facts/Df_(Unix)/XYWlcgm9">df</a></th><td>Filesystem</td><td>Mandatory</td><td>Report free disk space</td><td>Version 1 AT&T UNIX</td></tr><tr><th scope="row"><a href="/facts/Diff/MtzRWwql">diff</a></th><td>Text processing</td><td>Mandatory</td><td>Compare two files; see also cmp</td><td>Version 5 AT&T UNIX</td></tr><tr><th scope="row"><a href="/facts/Dirname/9hPPpb2a">dirname</a></th><td>Filesystem</td><td>Mandatory</td><td>Return the directory portion of a pathname; see also basename</td><td>System III</td></tr><tr><th scope="row"><a href="/facts/Du_(Unix)/ckVT5ceF">du</a></th><td>Filesystem</td><td>Mandatory</td><td>Estimate file space usage</td><td>Version 1 AT&T UNIX</td></tr><tr><th scope="row"><a href="/facts/Echo_(command)/ue5jH01X">echo</a></th><td>Shell programming</td><td>Mandatory</td><td>Write arguments to standard output</td><td>Version 2 AT&T UNIX</td></tr><tr><th scope="row"><a href="/facts/Ed_(text_editor)/a3lSk6Ry">ed</a></th><td>Text processing</td><td>Mandatory</td><td>The standard text editor</td><td>PDP-7 UNIX</td></tr><tr><th scope="row"><a href="/facts/Env_(shell)/nsV24QVl">env</a></th><td>Misc</td><td>Mandatory</td><td>Set the environment for command invocation</td><td>System III</td></tr><tr><th scope="row"><a href="/facts/Ex_(text_editor)/fMl34cby">ex</a></th><td>Text processing</td><td>Optional (UP)</td><td>Text editor</td><td>1BSD</td></tr><tr><th scope="row"><a href="/facts/Expand_(Unix)/vGf5qMkh">expand</a></th><td>Text processing</td><td>Mandatory</td><td>Convert tabs to spaces</td><td>3BSD</td></tr><tr><th scope="row"><a href="/facts/Expr/QCIoHt60">expr</a></th><td>Shell programming</td><td>Mandatory</td><td>Evaluate arguments as an expression</td><td>Version 7 AT&T UNIX</td></tr><tr><th scope="row"><a href="/facts/False_(Unix)/ju0HALI8">false</a></th><td>Shell programming</td><td>Mandatory</td><td>Return false value</td><td>Version 7 AT&T UNIX</td></tr><tr><th scope="row"><a href="/facts/Fc_(Unix)/74YGy3eY">fc</a></th><td>Misc</td><td>Optional (UP)</td><td>Process the command history list</td><td></td></tr><tr><th scope="row"><a href="/facts/Fg_(Unix)/NIzeWzjq">fg</a></th><td>Process management</td><td>Optional (UP)</td><td>Run jobs in the foreground</td><td></td></tr><tr><th scope="row"><a href="/facts/File_(command)/P5Nvve4C">file</a></th><td>Filesystem</td><td>Mandatory</td><td>Determine file type</td><td>Version 4 AT&T UNIX</td></tr><tr><th scope="row"><a href="/facts/Find_(Unix)/bg18ASlI">find</a></th><td>Filesystem</td><td>Mandatory</td><td>Find files</td><td>Version 1 AT&T UNIX</td></tr><tr><th scope="row"><a href="/facts/Fold_(Unix)/CPl4JycJ">fold</a></th><td>Text processing</td><td>Mandatory</td><td>Filter for folding lines</td><td>1BSD</td></tr><tr><th scope="row"><a href="/facts/Fuser_(Unix)/hbh3kaSI">fuser</a></th><td>Process management</td><td>Optional (XSI)</td><td>List <a href="/facts/Process_identifier/q9TlqHEP">process IDs</a> of all processes that have one or more files open</td><td>System V</td></tr><tr><th scope="row"><a href="/facts/Gencat/EEuIsUx9">gencat</a></th><td>Misc</td><td>Mandatory</td><td>Generate a formatted message catalog</td><td></td></tr><tr><th scope="row">get</th><td>SCCS</td><td>Optional (XSI)</td><td>Get a version of an SCCS file</td><td>PWB UNIX</td></tr><tr><th scope="row"><a href="/facts/Getconf/EEuIsUx9">getconf</a></th><td>Misc</td><td>Mandatory</td><td>Get configuration values</td><td></td></tr><tr><th scope="row"><a href="/facts/Getopts/Ju6xVkg2">getopts</a></th><td>Shell programming</td><td>Mandatory</td><td>Parse utility options</td><td></td></tr><tr><th scope="row"><a href="/facts/Gettext/ujpNUjg8">gettext</a></th><td>Misc</td><td>Mandatory</td><td>Retrieve text string from messages object</td><td></td></tr><tr><th scope="row"><a href="/facts/Grep/PdGQeFfD">grep</a></th><td>Misc</td><td>Mandatory</td><td>Search text for a pattern</td><td>Version 4 AT&T UNIX</td></tr><tr><th scope="row"><a href="/facts/Hash_(Unix)/q8zz11eU">hash</a></th><td>Misc</td><td>Mandatory</td><td>Hash database access method</td><td></td></tr><tr><th scope="row"><a href="/facts/Head_(Unix)/VADCHJTV">head</a></th><td>Text processing</td><td>Mandatory</td><td>Copy the first part of files</td><td>PWB UNIX</td></tr><tr><th scope="row"><a href="/facts/Iconv/8Asx4eA2">iconv</a></th><td>Text processing</td><td>Mandatory</td><td>Codeset conversion</td><td>HP-UX</td></tr><tr><th scope="row"><a href="/facts/Id_(Unix)/EEuIsUx9">id</a></th><td>Misc</td><td>Mandatory</td><td>Return user identity</td><td>System V</td></tr><tr><th scope="row"><a href="/facts/Ipcrm/AANx5cPz">ipcrm</a></th><td>Misc</td><td>Optional (XSI)</td><td>Remove a message queue, semaphore set, or shared memory segment identifier</td><td>System V</td></tr><tr><th scope="row"><a href="/facts/Ipcs/SAPvlaHn">ipcs</a></th><td>Misc</td><td>Optional (XSI)</td><td>Report interprocess communication facilities status</td><td>System V</td></tr><tr><th scope="row">jobs</th><td>Process management</td><td>Optional (UP)</td><td>Display status of jobs in the current session</td><td></td></tr><tr><th scope="row"><a href="/facts/Join_(Unix)/bI2dS0dJ">join</a></th><td>Text processing</td><td>Mandatory</td><td>Merges two sorted text files based on the presence of a common field</td><td>Version 7 AT&T UNIX</td></tr><tr><th scope="row"><a href="/facts/Kill_(command)/PjqmLTUR">kill</a></th><td>Process management</td><td>Mandatory</td><td>Terminate or signal processes</td><td>Version 4 AT&T UNIX</td></tr><tr><th scope="row"><a href="/facts/Lex_programming_tool/elaAUUIz">lex</a></th><td>C programming</td><td>Optional (CD)</td><td>Generate programs for <a href="/facts/Lexical_analyzer/T1JYWpIf">lexical tasks</a></td><td>Version 7 AT&T UNIX</td></tr><tr><th scope="row"><a href="/facts/Link_(Unix)/0Y1Cb1Az">link</a></th><td>Filesystem</td><td>Optional (XSI)</td><td>Create a hard link to a file</td><td>Version 1 AT&T UNIX</td></tr><tr><th scope="row"><a href="/facts/Ln_(Unix)/Ioq2y31h">ln</a></th><td>Filesystem</td><td>Mandatory</td><td>Link files</td><td>Version 1 AT&T UNIX</td></tr><tr><th scope="row">locale</th><td>Misc</td><td>Mandatory</td><td>Get locale-specific information</td><td></td></tr><tr><th scope="row"><a href="/facts/Localedef/EEuIsUx9">localedef</a></th><td>Misc</td><td>Mandatory</td><td>Define locale environment</td><td></td></tr><tr><th scope="row">logger</th><td>Shell programming</td><td>Mandatory</td><td>Log messages</td><td>4.3BSD</td></tr><tr><th scope="row"><a href="/facts/Logname/b0TXzaka">logname</a></th><td>Misc</td><td>Mandatory</td><td>Return the user's login name</td><td>4.4BSD</td></tr><tr><th scope="row"><a href="/facts/Lp_(Unix)/Xf6P8rCV">lp</a></th><td>Text processing</td><td>Mandatory</td><td>Send files to a printer</td><td>System V</td></tr><tr><th scope="row"><a href="/facts/Ls/5GsH3v2a">ls</a></th><td>Filesystem</td><td>Mandatory</td><td>List directory contents</td><td>Version 1 AT&T UNIX</td></tr><tr><th scope="row"><a href="/facts/M4_(computer_language)/Q4gX4ske">m4</a></th><td>Misc</td><td>Mandatory</td><td>Macro processor</td><td>PWB UNIX</td></tr><tr><th scope="row"><a href="/facts/Mailx/QMmV2M2J">mailx</a></th><td>Misc</td><td>Mandatory</td><td>Process messages</td><td>Version 1 AT&T UNIX</td></tr><tr><th scope="row"><a href="/facts/Make_(software)/5q1DQ4ot">make</a></th><td>Programming</td><td>Optional (SD)</td><td>Maintain, update, and regenerate groups of programs</td><td>PWB UNIX</td></tr><tr><th scope="row"><a href="/facts/Man_page/S2yYjy0J">man</a></th><td>Misc</td><td>Mandatory</td><td>Display system documentation</td><td>Version 2 AT&T UNIX</td></tr><tr><th scope="row"><a href="/facts/Mesg/jUT9fEz2">mesg</a></th><td>Misc</td><td>Mandatory</td><td>Permit or deny messages</td><td>Version 1 AT&T UNIX</td></tr><tr><th scope="row"><a href="/facts/Mkdir/YI42PsYJ">mkdir</a></th><td>Filesystem</td><td>Mandatory</td><td>Make directories</td><td>Version 1 AT&T UNIX</td></tr><tr><th scope="row"><a href="/facts/Mkfifo/g78xY9lC">mkfifo</a></th><td>Filesystem</td><td>Mandatory</td><td>Make <a href="/facts/FIFO_(computing_and_electronics)/RctvBNgE">FIFO</a> special files</td><td>4.4BSD[<i>dubious – discuss</i>]</td></tr><tr><th scope="row"><a href="/facts/More_(command)/emnMr8xz">more</a></th><td>Text processing</td><td>Optional (UP)</td><td>Display files on a page-by-page basis</td><td>3BSD</td></tr><tr><th scope="row"><a href="/facts/Msgfmt/ujpNUjg8">msgfmt</a></th><td>Misc</td><td>Mandatory</td><td>Create messages objects from messages object files</td><td></td></tr><tr><th scope="row"><a href="/facts/Mv_(Unix)/BScugd1B">mv</a></th><td>Filesystem</td><td>Mandatory</td><td>Move or rename files</td><td>Version 1 AT&T UNIX</td></tr><tr><th scope="row"><a href="/facts/Newgrp/EEuIsUx9">newgrp</a></th><td>Misc</td><td>Mandatory</td><td>Change to a new group</td><td>Version 6 AT&T UNIX</td></tr><tr><th scope="row"><a href="/facts/Gettext/ujpNUjg8">ngettext</a></th><td>Misc</td><td>Mandatory</td><td>Retrieve text string from messages object with plural form</td><td></td></tr><tr><th scope="row"><a href="/facts/Nice_(Unix)/TRfCer6a">nice</a></th><td>Process management</td><td>Mandatory</td><td>Invoke a utility with an altered nice value</td><td>Version 4 AT&T UNIX</td></tr><tr><th scope="row"><a href="/facts/Nl_(Unix)/6Hn7q0VD">nl</a></th><td>Text processing</td><td>Optional (XSI)</td><td>Line numbering filter</td><td>System III</td></tr><tr><th scope="row"><a href="/facts/Nm_(Unix)/msepYzgk">nm</a></th><td>C programming</td><td>Optional(SD, XSI)</td><td>Write the name list of an <a href="/facts/Object_file/sFBvosE4">object file</a></td><td>Version 1 AT&T UNIX</td></tr><tr><th scope="row"><a href="/facts/Nohup/fAdxfMJm">nohup</a></th><td>Process management</td><td>Mandatory</td><td>Invoke a utility immune to <a href="/facts/SIGHUP/bRC8UnTx">hangups</a></td><td>Version 4 AT&T UNIX</td></tr><tr><th scope="row"><a href="/facts/Od_(Unix)/eS8QjQSD">od</a></th><td>Misc</td><td>Mandatory</td><td>Dump files in various formats</td><td>Version 1 AT&T UNIX</td></tr><tr><th scope="row"><a href="/facts/Paste_(Unix)/pQbtMFVL">paste</a></th><td>Text processing</td><td>Mandatory</td><td>Merge corresponding or subsequent lines of files</td><td>Version 32V AT&T UNIX</td></tr><tr><th scope="row"><a href="/facts/Patch_(Unix)/9tFn5GeU">patch</a></th><td>Text processing</td><td>Mandatory</td><td>Apply changes to files</td><td>4.3BSD</td></tr><tr><th scope="row"><a href="/facts/Pathchk/EEuIsUx9">pathchk</a></th><td>Filesystem</td><td>Mandatory</td><td>Check pathnames</td><td></td></tr><tr><th scope="row"><a href="/facts/Pax_(command)/dPXpJaas">pax</a></th><td>Misc</td><td>Mandatory</td><td>Portable archive interchange</td><td>4.4BSD</td></tr><tr><th scope="row"><a href="/facts/Pr_(Unix)/Xwze4vfX">pr</a></th><td>Text processing</td><td>Mandatory</td><td>Paginate or columnate files for printing</td><td>Version 1 AT&T UNIX</td></tr><tr><th scope="row"><a href="/facts/Printf_(Unix)/uToyvMpD">printf</a></th><td>Shell programming</td><td>Mandatory</td><td>Write formatted output</td><td>4.3BSD-Reno</td></tr><tr><th scope="row">prs</th><td>SCCS</td><td>Optional (XSI)</td><td>Print an SCCS file</td><td>PWB UNIX</td></tr><tr><th scope="row"><a href="/facts/Ps_(Unix)/WWR5zQkC">ps</a></th><td>Process management</td><td>Mandatory</td><td>Report process status</td><td>Version 4 AT&T UNIX</td></tr><tr><th scope="row"><a href="/facts/Pwd/D8NjW3nY">pwd</a></th><td>Filesystem</td><td>Mandatory</td><td>Print working directory</td><td>Version 5 AT&T UNIX</td></tr><tr><th scope="row"><a href="/facts/Read_(Unix)/VeE1vuLL">read</a></th><td>Shell programming</td><td>Mandatory</td><td>Read a line from standard input</td><td></td></tr><tr><th scope="row"><a href="/facts/Readlink_(Unix)/EEuIsUx9">readlink</a></th><td>Filesystem</td><td>Mandatory</td><td>Print destination of a symbolic link</td><td></td></tr><tr><th scope="row">realpath</th><td>Filesystem</td><td>Mandatory</td><td>Resolve a symbolic link</td><td></td></tr><tr><th scope="row"><a href="/facts/Renice/TRfCer6a">renice</a></th><td>Process management</td><td>Mandatory</td><td>Set nice values of running processes</td><td>4BSD</td></tr><tr><th scope="row"><a href="/facts/Rm_(Unix)/FPB4Q2wM">rm</a></th><td>Filesystem</td><td>Mandatory</td><td>Remove directory entries</td><td>Version 1 AT&T UNIX</td></tr><tr><th scope="row"><a href="/facts/Rmdel/EEuIsUx9">rmdel</a></th><td>SCCS</td><td>Optional (XSI)</td><td>Remove a delta from an SCCS file</td><td>PWB UNIX</td></tr><tr><th scope="row"><a href="/facts/Rmdir/1dMYlg6C">rmdir</a></th><td>Filesystem</td><td>Mandatory</td><td>Remove directories, if they are empty.</td><td>Version 1 AT&T UNIX</td></tr><tr><th scope="row">sact</th><td>SCCS</td><td>Optional (XSI)</td><td>Print current SCCS file-editing activity</td><td>System III</td></tr><tr><th scope="row"><a href="/facts/Source_Code_Control_System/v85GIeBx">sccs</a></th><td><a href="/facts/Source_Code_Control_System/v85GIeBx">SCCS</a></td><td>Optional (XSI)</td><td>Front end for the SCCS subsystem</td><td>4.3BSD</td></tr><tr><th scope="row"><a href="/facts/Sed/5pXUwRdD">sed</a></th><td>Text processing</td><td>Mandatory</td><td>Stream editor</td><td>Version 7 AT&T UNIX</td></tr><tr><th scope="row"><a href="/facts/Bourne_shell/wUCh3Qkl">sh</a></th><td>Shell programming</td><td>Mandatory</td><td><a href="/facts/Unix_shell/2G4T2Fb9">Shell</a>, the standard command language interpreter</td><td>Version 7 AT&T UNIX(in earlier versions, sh was either the <a href="/facts/Thompson_shell/qISwy6xJ">Thompson shell</a> or the <a href="/facts/PWB_shell/DbnGb8A5">PWB shell</a>)</td></tr><tr><th scope="row"><a href="/facts/Sleep_(command)/pghbFcxl">sleep</a></th><td>Shell programming</td><td>Mandatory</td><td>Suspend execution for an interval</td><td>Version 4 AT&T UNIX</td></tr><tr><th scope="row"><a href="/facts/Sort_(Unix)/oa9wxsq2">sort</a></th><td>Text processing</td><td>Mandatory</td><td>Sort, merge, or sequence check text files</td><td>Version 1 AT&T UNIX</td></tr><tr><th scope="row"><a href="/facts/Split_(Unix)/k0lPCYva">split</a></th><td>Misc</td><td>Mandatory</td><td>Split files into pieces</td><td>Version 3 AT&T UNIX</td></tr><tr><th scope="row"><a href="/facts/Strings_(Unix)/UCdWfNET">strings</a></th><td>C programming</td><td>Mandatory</td><td>Find printable strings in files</td><td>2BSD</td></tr><tr><th scope="row"><a href="/facts/Strip_(Unix)/qNQd9fgu">strip</a></th><td>C programming</td><td>Optional (SD)</td><td>Remove unnecessary information from executable files</td><td>Version 1 AT&T UNIX</td></tr><tr><th scope="row">stty</th><td>Misc</td><td>Mandatory</td><td>Set the options for a terminal</td><td>Version 2 AT&T UNIX</td></tr><tr><th scope="row">tabs</th><td>Misc</td><td>Mandatory</td><td>Set terminal tabs</td><td>PWB UNIX</td></tr><tr><th scope="row"><a href="/facts/Tail_(Unix)/g6xRo1nd">tail</a></th><td>Text processing</td><td>Mandatory</td><td>Copy the last part of a file</td><td>PWB UNIX</td></tr><tr><th scope="row"><a href="/facts/Talk_(software)/wue3ElaT">talk</a></th><td>Misc</td><td>Optional (UP)</td><td>Talk to another user</td><td>4.2BSD</td></tr><tr><th scope="row"><a href="/facts/Tee_(command)/EvXj51Sw">tee</a></th><td>Shell programming</td><td>Mandatory</td><td>Duplicate the <a href="/facts/Standard_streams/r92M7Wd4">standard output</a></td><td>Version 5 AT&T UNIX</td></tr><tr><th scope="row"><a href="/facts/Test_(Unix)/r7uIjBmz">test</a></th><td>Shell programming</td><td>Mandatory</td><td>Evaluate <a href="/facts/Expression_(computer_science)/eRlhoBeN">expression</a></td><td>Version 7 AT&T UNIX</td></tr><tr><th scope="row"><a href="/facts/Time_(Unix)/Xac3gVDE">time</a></th><td>Process management</td><td>Mandatory</td><td>Display elapsed, system and kernel time used by the current shell or designated process.</td><td>Version 3 AT&T UNIX<a class="footnote-ref" id="fnref:1" href="#fn:1"><sup>1</sup></a></td></tr><tr><th scope="row">timeout</th><td>Process management</td><td>Mandatory</td><td>Run command with a time limit</td><td>Version 3 AT&T UNIX</td></tr><tr><th scope="row"><a href="/facts/Touch_(command)/3yXqX9Aa">touch</a></th><td>Filesystem</td><td>Mandatory</td><td>Change file access and modification times</td><td>Version 7 AT&T UNIX</td></tr><tr><th scope="row"><a href="/facts/Tput/ts7xW2Iy">tput</a></th><td>Misc</td><td>Mandatory</td><td>Change <a href="/facts/Computer_terminal/fSlx05qV">terminal</a> characteristics</td><td>System V</td></tr><tr><th scope="row"><a href="/facts/Tr_(Unix)/Ev2SREmK">tr</a></th><td>Text processing</td><td>Mandatory</td><td>Translate characters</td><td>Version 4 AT&T UNIX</td></tr><tr><th scope="row"><a href="/facts/True_(Unix)/ju0HALI8">true</a></th><td>Shell programming</td><td>Mandatory</td><td>Return true value</td><td>Version 7 AT&T UNIX</td></tr><tr><th scope="row"><a href="/facts/Tsort_(Unix)/TIkWzlnn">tsort</a></th><td>Text processing</td><td>Mandatory</td><td>Topological sort</td><td>Version 7 AT&T UNIX</td></tr><tr><th scope="row"><a href="/facts/Tty_(unix)/czsCkfWP">tty</a></th><td>Misc</td><td>Mandatory</td><td>Return user's <a href="/facts/Computer_terminal/fSlx05qV">terminal</a> name</td><td>Version 1 AT&T UNIX</td></tr><tr><th scope="row"><a href="/facts/Type_(Unix)/dNxYbnDF">type</a></th><td>Misc</td><td>Optional (XSI)</td><td>Displays how a name would be interpreted if used as a command</td><td></td></tr><tr><th scope="row">ulimit</th><td>Misc</td><td>Optional (XSI)</td><td>Set or report file size limit</td><td></td></tr><tr><th scope="row"><a href="/facts/Umask/guGm0ye9">umask</a></th><td>Misc</td><td>Mandatory</td><td>Get or set the file mode creation mask</td><td>System III</td></tr><tr><th scope="row"><a href="/facts/Unalias/BL5hJMxl">unalias</a></th><td>Misc</td><td>Mandatory</td><td>Remove alias definitions</td><td></td></tr><tr><th scope="row"><a href="/facts/Uname/fx63hv3C">uname</a></th><td>Misc</td><td>Mandatory</td><td>Return system name</td><td>PWB UNIX</td></tr><tr><th scope="row"><a href="/facts/Uncompress/RLSgGNUX">uncompress</a></th><td>Misc</td><td>Optional (XSI)</td><td>Expand compressed data</td><td>4.3BSD</td></tr><tr><th scope="row"><a href="/facts/Unexpand/uJIAzdqr">unexpand</a></th><td>Text processing</td><td>Mandatory</td><td>Convert spaces to tabs</td><td>3BSD</td></tr><tr><th scope="row">unget</th><td>SCCS</td><td>Optional (XSI)</td><td>Undo a previous get of an SCCS file</td><td>System III</td></tr><tr><th scope="row"><a href="/facts/Uniq/jNKDdY7M">uniq</a></th><td>Text processing</td><td>Mandatory</td><td>Report or filter out repeated lines in a file</td><td>Version 3 AT&T UNIX</td></tr><tr><th scope="row"><a href="/facts/Unlink_(Unix)/YKat5WFM">unlink</a></th><td>Filesystem</td><td>Optional (XSI)</td><td>Call the unlink function</td><td>Version 1 AT&T UNIX</td></tr><tr><th scope="row"><a href="/facts/Uucp/dQ055F7b">uucp</a></th><td>Network</td><td>Optional (UU)</td><td>System-to-system copy</td><td>Version 7 AT&T UNIX</td></tr><tr><th scope="row"><a href="/facts/Uudecode/lEjGENqK">uudecode</a></th><td>Network</td><td>Mandatory</td><td>Decode a binary file</td><td>4BSD</td></tr><tr><th scope="row"><a href="/facts/Uuencode/lEjGENqK">uuencode</a></th><td>Network</td><td>Mandatory</td><td>Encode a binary file</td><td>4BSD</td></tr><tr><th scope="row"><a href="/facts/Uustat/dQ055F7b">uustat</a></th><td>Network</td><td>Optional (UU)</td><td><a href="/facts/Uucp/dQ055F7b">uucp</a> status inquiry and job control</td><td>System III</td></tr><tr><th scope="row">uux</th><td>Process management</td><td>Optional (UU)</td><td>Remote command execution</td><td>Version 7 AT&T UNIX</td></tr><tr><th scope="row">val</th><td>SCCS</td><td>Optional (XSI)</td><td>Validate SCCS files</td><td>System III</td></tr><tr><th scope="row"><a href="/facts/Vi_(text_editor)/d8G1PkDh">vi</a></th><td>Text processing</td><td>Optional (UP)</td><td>Screen-oriented (visual) display editor</td><td>1BSD</td></tr><tr><th scope="row"><a href="/facts/Wait_(command)/WByDwJCn">wait</a></th><td>Process management</td><td>Mandatory</td><td>Await process completion</td><td>Version 4 AT&T UNIX</td></tr><tr><th scope="row"><a href="/facts/Wc_(Unix)/XxRPj8b1">wc</a></th><td>Text processing</td><td>Mandatory</td><td>Line, word and byte or character count</td><td>Version 1 AT&T UNIX</td></tr><tr><th scope="row">what</th><td><a href="/facts/Source_Code_Control_System/v85GIeBx">SCCS</a></td><td>Optional (XSI)</td><td>Identify SCCS files</td><td>PWB UNIX</td></tr><tr><th scope="row"><a href="/facts/Who_(Unix)/3XnJumIz">who</a></th><td>System administration</td><td>Optional (XSI)</td><td>Display who is on the system</td><td>Version 1 AT&T UNIX</td></tr><tr><th scope="row"><a href="/facts/Write_(Unix)/WSEkhguY">write</a></th><td>Misc</td><td>Mandatory</td><td>Write to another user's terminal</td><td>Version 1 AT&T UNIX</td></tr><tr><th scope="row"><a href="/facts/Xargs/nXhrdwXI">xargs</a></th><td>Shell programming</td><td>Mandatory</td><td>Construct argument lists and invoke utility</td><td>PWB UNIX</td></tr><tr><th scope="row"><a href="/facts/Gettext/ujpNUjg8">xgettext</a></th><td>C programming</td><td>Optional (CD)</td><td>Extract gettext calls from C source code strings</td><td>IEEE Std 1003.1-2024</td></tr><tr><th scope="row"><a href="/facts/Yacc/sXp5I7Tw">yacc</a></th><td>C programming</td><td>Optional (CD)</td><td>Yet another <a href="/facts/Compiler/WNfCDFJe">compiler</a> compiler</td><td>PWB UNIX</td></tr><tr><th scope="row"><a href="/facts/Zcat/H23uqvyx">zcat</a></th><td>Text processing</td><td>Optional (XSI)</td><td>Expand and concatenate data</td><td>4.3BSD</td></tr></tbody></table> <h2 id="see-also">See also</h2> <ul><li><a href="/facts/List_of_GNU_Core_Utilities_commands/pQlS09fd">List of GNU Core Utilities commands</a></li> <li><a href="/facts/GNOME_Core_Applications/bC6GBU4G">GNOME Core Applications</a></li> <li><a href="/facts/List_of_GNU_packages/5JajRxQo">List of GNU packages</a></li> <li><a href="/facts/List_of_KDE_applications/PW6RokRK">List of KDE applications</a></li> <li><a href="/facts/List_of_Unix_daemons/EFxhNpfu">List of Unix daemons</a></li> <li><a href="/facts/Unix_philosophy/U2WTavT0">Unix philosophy</a></li> <li><a href="/facts/Util-linux/vPHnV2Iy">util-linux</a></li></ul> <h2 id="external-links">External links</h2> The Wikibook <i>Guide to UNIX</i> has a page on the topic of: <i>Commands</i> Wikimedia Commons has media related to Unix reference cards. <ul><li><a href="https://pubs.opengroup.org/onlinepubs/000095399/">IEEE Std 1003.1,2004 specifications</a></li> <li><a href="https://pubs.opengroup.org/onlinepubs/9699919799/">IEEE Std 1003.1,2008 specifications</a></li> <li><a href="https://pubs.opengroup.org/onlinepubs/9799919799/">IEEE Std 1003.1,2024 specifications</a></li> <li><a href="https://bhami.com/rosetta.html">Rosetta Stone For *Nix</a> – configurable list of equivalent programs for *nix systems.</li> <li><a href="http://roesler-ac.de/wolfram/acro/Cmd.htm">The Unix Acronym List: Unix Commands</a> – explains the names of many Unix commands.</li></ul> <h2 id="references">References</h2> <ol> <li id="fn:1"><p>"FreeBSD Manual Pages: time". man.freebsd.org. July 7, 202. Retrieved Mar 23, 2025. <a href="https://man.freebsd.org/cgi/man.cgi?query=time" target="_blank">https://man.freebsd.org/cgi/man.cgi?query=time</a> <a href="#fnref:1" class="footnote-back-ref">↩</a></p></li> </ol>