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<!DOCTYPE html> <html> <head> <meta charset="UTF-8"/> <meta name="viewport" content="width=device-width, initial-scale=1.0"> <link rel="stylesheet" href="/mandoc.css" type="text/css" media="all"> <title>apropos(1) - OpenBSD manual pages</title> </head> <body> <header> <section> <h1><a href="https://www.openbsd.org/">OpenBSD</a> manual page server</h1> </section> <form role="search" action="/" method="get" autocomplete="off" autocapitalize="none"> <fieldset> <legend>Manual Page Search Parameters</legend> <label>Search query: <input type="search" name="query" value="apropos" size="40"> </label> <button type="submit" name="apropos" value="0">man</button> <button type="submit" name="apropos" value="1">apropos</button> <br/> <select name="sec" aria-label="Manual section"> <option value="0">All Sections</option> <option value="1" selected="selected">1 - General Commands</option> <option value="2">2 - System Calls</option> <option value="3">3 - Library Functions</option> <option value="3p">3p - Perl Library</option> <option value="4">4 - Device Drivers</option> <option value="5">5 - File Formats</option> <option value="6">6 - Games</option> <option value="7">7 - Miscellaneous Information</option> <option value="8">8 - System Manager's Manual</option> <option value="9">9 - Kernel Developer's Manual</option> </select> <select name="arch" aria-label="CPU architecture"> <option value="default" selected="selected">All Architectures</option> <option>amd64</option> <option>alpha</option> <option>armv7</option> <option>arm64</option> <option>hppa</option> <option>i386</option> <option>landisk</option> <option>loongson</option> <option>luna88k</option> <option>macppc</option> <option>mips64</option> <option>octeon</option> <option>powerpc64</option> <option>riscv64</option> <option>sparc64</option> <option>amiga</option> <option>arc</option> <option>armish</option> <option>arm32</option> <option>atari</option> <option>aviion</option> <option>beagle</option> <option>cats</option> <option>hppa64</option> <option>hp300</option> <option>ia64</option> <option>mac68k</option> <option>mvme68k</option> <option>mvme88k</option> <option>mvmeppc</option> <option>palm</option> <option>pc532</option> <option>pegasos</option> <option>pmax</option> <option>powerpc</option> <option>sgi</option> <option>socppc</option> <option>solbourne</option> <option>sparc</option> <option>sun3</option> <option>vax</option> <option>wgrisc</option> <option>x68k</option> <option>zaurus</option> </select> <select name="manpath" aria-label="Manual path"> <option selected="selected">OpenBSD-current</option> <option>OpenBSD-7.6</option> <option>OpenBSD-7.5</option> <option>OpenBSD-7.4</option> <option>OpenBSD-7.3</option> <option>OpenBSD-7.2</option> <option>OpenBSD-7.1</option> <option>OpenBSD-7.0</option> <option>OpenBSD-6.9</option> <option>OpenBSD-6.8</option> <option>OpenBSD-6.7</option> <option>OpenBSD-6.6</option> <option>OpenBSD-6.5</option> <option>OpenBSD-6.4</option> <option>OpenBSD-6.3</option> <option>OpenBSD-6.2</option> <option>OpenBSD-6.1</option> <option>OpenBSD-6.0</option> <option>OpenBSD-5.9</option> <option>OpenBSD-5.8</option> <option>OpenBSD-5.7</option> <option>OpenBSD-5.6</option> <option>OpenBSD-5.5</option> <option>OpenBSD-5.4</option> <option>OpenBSD-5.3</option> <option>OpenBSD-5.2</option> <option>OpenBSD-5.1</option> <option>OpenBSD-5.0</option> <option>OpenBSD-4.9</option> <option>OpenBSD-4.8</option> <option>OpenBSD-4.7</option> <option>OpenBSD-4.6</option> <option>OpenBSD-4.5</option> <option>OpenBSD-4.4</option> <option>OpenBSD-4.3</option> <option>OpenBSD-4.2</option> <option>OpenBSD-4.1</option> <option>OpenBSD-4.0</option> <option>OpenBSD-3.9</option> <option>OpenBSD-3.8</option> <option>OpenBSD-3.7</option> <option>OpenBSD-3.6</option> <option>OpenBSD-3.5</option> <option>OpenBSD-3.4</option> <option>OpenBSD-3.3</option> <option>OpenBSD-3.2</option> <option>OpenBSD-3.1</option> <option>OpenBSD-3.0</option> <option>OpenBSD-2.9</option> <option>OpenBSD-2.8</option> <option>OpenBSD-2.7</option> <option>OpenBSD-2.6</option> <option>OpenBSD-2.5</option> <option>OpenBSD-2.4</option> <option>OpenBSD-2.3</option> <option>OpenBSD-2.2</option> </select> </fieldset> </form> </header> <hr> <div class="head" role="doc-pageheader" aria-label="Manual header line"><span class="head-ltitle">APROPOS(1)</span> <span class="head-vol">General Commands Manual</span> <span class="head-rtitle">APROPOS(1)</span></div> <main class="manual-text"> <section class="Sh"> <h2 class="Sh" id="NAME"><a class="permalink" href="#NAME">NAME</a></h2> <p class="Pp"><code class="Nm">apropos</code>, <code class="Nm">whatis</code> — <span class="Nd" role="doc-subtitle">search manual page databases</span></p> </section> <section class="Sh"> <h2 class="Sh" id="SYNOPSIS"><a class="permalink" href="#SYNOPSIS">SYNOPSIS</a></h2> <table class="Nm"> <tr> <td><code class="Nm">apropos</code></td> <td>[<code class="Fl">-afk</code>] [<code class="Fl">-C</code> <var class="Ar">file</var>] [<code class="Fl">-M</code> <var class="Ar">path</var>] [<code class="Fl">-m</code> <var class="Ar">path</var>] [<code class="Fl">-O</code> <var class="Ar">outkey</var>] [<code class="Fl">-S</code> <var class="Ar">arch</var>] [<code class="Fl">-s</code> <var class="Ar">section</var>] <var class="Ar">expression ...</var></td> </tr> </table> </section> <section class="Sh"> <h2 class="Sh" id="DESCRIPTION"><a class="permalink" href="#DESCRIPTION">DESCRIPTION</a></h2> <p class="Pp">The <code class="Nm">apropos</code> and <code class="Nm">whatis</code> utilities query manual page databases generated by <a class="Xr" href="/makewhatis.8" aria-label="makewhatis, section 8">makewhatis(8)</a>, evaluating <var class="Ar">expression</var> for each file in each database. By default, they display the names, section numbers, and description lines of all matching manuals.</p> <p class="Pp">By default, <code class="Nm">apropos</code> searches for <a class="Xr" href="/makewhatis.8" aria-label="makewhatis, section 8">makewhatis(8)</a> databases in the default paths stipulated by <a class="Xr" href="/man.1" aria-label="man, section 1">man(1)</a> and uses case-insensitive extended regular expression matching over manual names and descriptions (the <code class="Li">Nm</code> <span class="No">and</span> <code class="Li">Nd</code> <span class="No">macro keys</span>). Multiple terms imply pairwise <code class="Fl">-o</code>.</p> <p class="Pp"><code class="Nm">whatis</code> is a synonym for <code class="Nm">apropos</code> <code class="Fl">-f</code>.</p> <p class="Pp">The options are as follows:</p> <dl class="Bl-tag"> <dt id="a"><a class="permalink" href="#a"><code class="Fl">-a</code></a></dt> <dd>Instead of showing only the title lines, show the complete manual pages, just like <a class="Xr" href="/man.1" aria-label="man, section 1">man(1)</a> <code class="Fl">-a</code> would. If the standard output is a terminal device and <code class="Fl">-c</code> is not specified, use <a class="Xr" href="/less.1" aria-label="less, section 1">less(1)</a> to paginate them. In <code class="Fl">-a</code> mode, the options <code class="Fl">-IKOTW</code> described in the <a class="Xr" href="/mandoc.1" aria-label="mandoc, section 1">mandoc(1)</a> manual are also available.</dd> <dt id="C"><a class="permalink" href="#C"><code class="Fl">-C</code></a> <var class="Ar">file</var></dt> <dd>Specify an alternative configuration <var class="Ar">file</var> in <a class="Xr" href="/man.conf.5" aria-label="man.conf, section 5">man.conf(5)</a> format.</dd> <dt id="f"><a class="permalink" href="#f"><code class="Fl">-f</code></a></dt> <dd>Search for all words in <var class="Ar">expression</var> in manual page names only. The search is case-insensitive and matches whole words only. In this mode, macro keys, comparison operators, and logical operators are not available.</dd> <dt id="k"><a class="permalink" href="#k"><code class="Fl">-k</code></a></dt> <dd>Support the full <var class="Ar">expression</var> syntax. It is the default for <code class="Nm">apropos</code>.</dd> <dt id="M"><a class="permalink" href="#M"><code class="Fl">-M</code></a> <var class="Ar">path</var></dt> <dd>Use the colon-separated path instead of the default list of paths searched for <a class="Xr" href="/makewhatis.8" aria-label="makewhatis, section 8">makewhatis(8)</a> databases. Invalid paths, or paths without manual databases, are ignored.</dd> <dt id="m"><a class="permalink" href="#m"><code class="Fl">-m</code></a> <var class="Ar">path</var></dt> <dd>Prepend the colon-separated paths to the list of paths searched for <a class="Xr" href="/makewhatis.8" aria-label="makewhatis, section 8">makewhatis(8)</a> databases. Invalid paths, or paths without manual databases, are ignored.</dd> <dt id="O"><a class="permalink" href="#O"><code class="Fl">-O</code></a> <var class="Ar">outkey</var></dt> <dd>Show the values associated with the key <var class="Ar">outkey</var> instead of the manual descriptions.</dd> <dt id="S"><a class="permalink" href="#S"><code class="Fl">-S</code></a> <var class="Ar">arch</var></dt> <dd>Restrict the search to pages for the specified <a class="Xr" href="/machine.1" aria-label="machine, section 1">machine(1)</a> architecture. <var class="Ar">arch</var> is case-insensitive. By default, pages for all architectures are shown.</dd> <dt id="s"><a class="permalink" href="#s"><code class="Fl">-s</code></a> <var class="Ar">section</var></dt> <dd>Restrict the search to the specified section of the manual. By default, pages from all sections are shown. See <a class="Xr" href="/man.1" aria-label="man, section 1">man(1)</a> for a listing of sections.</dd> </dl> <p class="Pp">The options <code class="Fl">-chlw</code> are also supported and are documented in <a class="Xr" href="/man.1" aria-label="man, section 1">man(1)</a>. The options <code class="Fl">-fkl</code> are mutually exclusive and override each other.</p> <p class="Pp">An <var class="Ar">expression</var> consists of search terms joined by logical operators <code class="Fl">-a</code> (and) and <code class="Fl">-o</code> (or). The <code class="Fl">-a</code> operator has precedence over <code class="Fl">-o</code> and both are evaluated left-to-right.</p> <dl class="Bl-tag"> <dt>( <var class="Ar">expr</var> <span class="No">)</span></dt> <dd>True if the subexpression <var class="Ar">expr</var> is true.</dd> <dt><var class="Ar">expr1</var> <code class="Fl">-a</code> <var class="Ar">expr2</var></dt> <dd>True if both <var class="Ar">expr1</var> and <var class="Ar">expr2</var> are true (logical ‘and’).</dd> <dt><var class="Ar">expr1</var> [<code class="Fl">-o</code>] <var class="Ar">expr2</var></dt> <dd>True if <var class="Ar">expr1</var> and/or <var class="Ar">expr2</var> evaluate to true (logical ‘or’).</dd> <dt><var class="Ar">term</var></dt> <dd>True if <var class="Ar">term</var> is satisfied. This has syntax [[<var class="Ar">key</var>[,<var class="Ar">key...</var>]](<code class="Cm">=</code>|<code class="Cm">~</code>)]<var class="Ar">val</var>, where <var class="Ar">key</var> is an <a class="Xr" href="/mdoc.7" aria-label="mdoc, section 7">mdoc(7)</a> macro to query and <var class="Ar">val</var> is its value. See <a class="Sx" href="#Macro_Keys">Macro Keys</a> for a list of available keys. Operator <code class="Cm">=</code> evaluates a substring, while <code class="Cm">~</code> evaluates a case-sensitive extended regular expression.</dd> <dt id="i"><a class="permalink" href="#i"><code class="Fl">-i</code></a> <var class="Ar">term</var></dt> <dd>If <var class="Ar">term</var> is a regular expression, it is evaluated case-insensitively. Has no effect on substring terms.</dd> </dl> <p class="Pp">Results are sorted first according to the section number in ascending numerical order, then by the page name in ascending <a class="Xr" href="/ascii.7" aria-label="ascii, section 7">ascii(7)</a> alphabetical order, case-insensitive.</p> <p class="Pp">Each output line is formatted as</p> <p class="Pp"></p> <div class="Bd Bd-indent">name[, name...](sec) - description</div> <p class="Pp">Where “name” is the manual's name, “sec” is the manual section, and “description” is the manual's short description. If an architecture is specified for the manual, it is displayed as</p> <p class="Pp"></p> <div class="Bd Bd-indent">name(sec/arch) - description</div> <p class="Pp">Resulting manuals may be accessed as</p> <p class="Pp"></p> <div class="Bd Bd-indent"><code class="Li">$ man -s sec name</code></div> <p class="Pp">If an architecture is specified in the output, use</p> <p class="Pp"></p> <div class="Bd Bd-indent"><code class="Li">$ man -s sec -S arch name</code></div> <section class="Ss"> <h3 class="Ss" id="Macro_Keys"><a class="permalink" href="#Macro_Keys">Macro Keys</a></h3> <p class="Pp">Queries evaluate over a subset of <a class="Xr" href="/mdoc.7" aria-label="mdoc, section 7">mdoc(7)</a> macros indexed by <a class="Xr" href="/makewhatis.8" aria-label="makewhatis, section 8">makewhatis(8)</a>. In addition to the macro keys listed below, the special key <code class="Cm">any</code> may be used to match any available macro key.</p> <p class="Pp">Names and description:</p> <table class="Bl-column Bd-indent Bl-compact"> <tr id="Nm"> <td><a class="permalink" href="#Nm"><code class="Li">Nm</code></a></td> <td>manual name</td> </tr> <tr id="Nd"> <td><a class="permalink" href="#Nd"><code class="Li">Nd</code></a></td> <td>one-line manual description</td> </tr> <tr id="arch"> <td><a class="permalink" href="#arch"><code class="Li">arch</code></a></td> <td>machine architecture (case-insensitive)</td> </tr> <tr id="sec"> <td><a class="permalink" href="#sec"><code class="Li">sec</code></a></td> <td>manual section number</td> </tr> </table> <p class="Pp">Sections and cross references:</p> <table class="Bl-column Bd-indent Bl-compact"> <tr id="Sh"> <td><a class="permalink" href="#Sh"><code class="Li">Sh</code></a></td> <td>section header (excluding standard sections)</td> </tr> <tr id="Ss"> <td><a class="permalink" href="#Ss"><code class="Li">Ss</code></a></td> <td>subsection header</td> </tr> <tr id="Xr"> <td><a class="permalink" href="#Xr"><code class="Li">Xr</code></a></td> <td>cross reference to another manual page</td> </tr> <tr id="Rs"> <td><a class="permalink" href="#Rs"><code class="Li">Rs</code></a></td> <td>bibliographic reference</td> </tr> </table> <p class="Pp">Semantic markup for command line utilities:</p> <table class="Bl-column Bd-indent Bl-compact"> <tr id="Fl"> <td><a class="permalink" href="#Fl"><code class="Li">Fl</code></a></td> <td>command line options (flags)</td> </tr> <tr id="Cm"> <td><a class="permalink" href="#Cm"><code class="Li">Cm</code></a></td> <td>command modifier</td> </tr> <tr id="Ar"> <td><a class="permalink" href="#Ar"><code class="Li">Ar</code></a></td> <td>command argument</td> </tr> <tr id="Ic"> <td><a class="permalink" href="#Ic"><code class="Li">Ic</code></a></td> <td>internal or interactive command</td> </tr> <tr id="Ev"> <td><a class="permalink" href="#Ev"><code class="Li">Ev</code></a></td> <td>environmental variable</td> </tr> <tr id="Pa"> <td><a class="permalink" href="#Pa"><code class="Li">Pa</code></a></td> <td>file system path</td> </tr> </table> <p class="Pp">Semantic markup for function libraries:</p> <table class="Bl-column Bd-indent Bl-compact"> <tr id="Lb"> <td><a class="permalink" href="#Lb"><code class="Li">Lb</code></a></td> <td>function library name</td> </tr> <tr id="In"> <td><a class="permalink" href="#In"><code class="Li">In</code></a></td> <td>include file</td> </tr> <tr id="Ft"> <td><a class="permalink" href="#Ft"><code class="Li">Ft</code></a></td> <td>function return type</td> </tr> <tr id="Fn"> <td><a class="permalink" href="#Fn"><code class="Li">Fn</code></a></td> <td>function name</td> </tr> <tr id="Fa"> <td><a class="permalink" href="#Fa"><code class="Li">Fa</code></a></td> <td>function argument type and name</td> </tr> <tr id="Vt"> <td><a class="permalink" href="#Vt"><code class="Li">Vt</code></a></td> <td>variable type</td> </tr> <tr id="Va"> <td><a class="permalink" href="#Va"><code class="Li">Va</code></a></td> <td>variable name</td> </tr> <tr id="Dv"> <td><a class="permalink" href="#Dv"><code class="Li">Dv</code></a></td> <td>defined variable or preprocessor constant</td> </tr> <tr id="Er"> <td><a class="permalink" href="#Er"><code class="Li">Er</code></a></td> <td>error constant</td> </tr> <tr id="Ev~2"> <td><a class="permalink" href="#Ev~2"><code class="Li">Ev</code></a></td> <td>environmental variable</td> </tr> </table> <p class="Pp">Various semantic markup:</p> <table class="Bl-column Bd-indent Bl-compact"> <tr id="An"> <td><a class="permalink" href="#An"><code class="Li">An</code></a></td> <td>author name</td> </tr> <tr id="Lk"> <td><a class="permalink" href="#Lk"><code class="Li">Lk</code></a></td> <td>hyperlink</td> </tr> <tr id="Mt"> <td><a class="permalink" href="#Mt"><code class="Li">Mt</code></a></td> <td>“mailto” hyperlink</td> </tr> <tr id="Cd"> <td><a class="permalink" href="#Cd"><code class="Li">Cd</code></a></td> <td>kernel configuration declaration</td> </tr> <tr id="Ms"> <td><a class="permalink" href="#Ms"><code class="Li">Ms</code></a></td> <td>mathematical symbol</td> </tr> <tr id="Tn"> <td><a class="permalink" href="#Tn"><code class="Li">Tn</code></a></td> <td>tradename</td> </tr> </table> <p class="Pp">Physical markup:</p> <table class="Bl-column Bd-indent Bl-compact"> <tr id="Em"> <td><a class="permalink" href="#Em"><code class="Li">Em</code></a></td> <td>italic font or underline</td> </tr> <tr id="Sy"> <td><a class="permalink" href="#Sy"><code class="Li">Sy</code></a></td> <td>boldface font</td> </tr> <tr id="Li"> <td><a class="permalink" href="#Li"><code class="Li">Li</code></a></td> <td>typewriter font</td> </tr> </table> <p class="Pp">Text production:</p> <table class="Bl-column Bd-indent Bl-compact"> <tr id="St"> <td><a class="permalink" href="#St"><code class="Li">St</code></a></td> <td>reference to a standards document</td> </tr> <tr id="At"> <td><a class="permalink" href="#At"><code class="Li">At</code></a></td> <td><span class="Ux">AT&T UNIX</span> <span class="No">version reference</span></td> </tr> <tr id="Bx"> <td><a class="permalink" href="#Bx"><code class="Li">Bx</code></a></td> <td><span class="Ux">BSD</span> <span class="No">version reference</span></td> </tr> <tr id="Bsx"> <td><a class="permalink" href="#Bsx"><code class="Li">Bsx</code></a></td> <td><span class="Ux">BSD/OS</span> <span class="No">version reference</span></td> </tr> <tr id="Nx"> <td><a class="permalink" href="#Nx"><code class="Li">Nx</code></a></td> <td><span class="Ux">NetBSD</span> <span class="No">version reference</span></td> </tr> <tr id="Fx"> <td><a class="permalink" href="#Fx"><code class="Li">Fx</code></a></td> <td><span class="Ux">FreeBSD</span> <span class="No">version reference</span></td> </tr> <tr id="Ox"> <td><a class="permalink" href="#Ox"><code class="Li">Ox</code></a></td> <td><span class="Ux">OpenBSD</span> <span class="No">version reference</span></td> </tr> <tr id="Dx"> <td><a class="permalink" href="#Dx"><code class="Li">Dx</code></a></td> <td><span class="Ux">DragonFly</span> <span class="No">version reference</span></td> </tr> </table> <p class="Pp">In general, macro keys are supposed to yield complete results without expecting the user to consider actual macro usage. For example, results include:</p> <p class="Pp"></p> <div class="Bd-indent"> <dl class="Bl-tag Bl-compact"> <dt id="Fa~2"><a class="permalink" href="#Fa~2"><code class="Li">Fa</code></a></dt> <dd>function arguments appearing on <code class="Ic">Fn</code> lines</dd> <dt id="Fn~2"><a class="permalink" href="#Fn~2"><code class="Li">Fn</code></a></dt> <dd>function names marked up with <code class="Ic">Fo</code> macros</dd> <dt id="In~2"><a class="permalink" href="#In~2"><code class="Li">In</code></a></dt> <dd>include file names marked up with <code class="Ic">Fd</code> macros</dd> <dt id="Vt~2"><a class="permalink" href="#Vt~2"><code class="Li">Vt</code></a></dt> <dd>types appearing as function return types and</dd> <dt></dt> <dd>types appearing in function arguments in the SYNOPSIS</dd> </dl> </div> </section> </section> <section class="Sh"> <h2 class="Sh" id="ENVIRONMENT"><a class="permalink" href="#ENVIRONMENT">ENVIRONMENT</a></h2> <dl class="Bl-tag"> <dt id="MANPAGER"><a class="permalink" href="#MANPAGER"><code class="Ev">MANPAGER</code></a></dt> <dd>Any non-empty value of the environment variable <code class="Ev">MANPAGER</code> is used instead of the standard pagination program, <a class="Xr" href="/less.1" aria-label="less, section 1">less(1)</a>; see <a class="Xr" href="/man.1" aria-label="man, section 1">man(1)</a> for details. Only used if <code class="Fl">-a</code> or <code class="Fl">-l</code> is specified.</dd> <dt id="MANPATH"><a class="permalink" href="#MANPATH"><code class="Ev">MANPATH</code></a></dt> <dd>A colon-separated list of directories to search for manual pages; see <a class="Xr" href="/man.1" aria-label="man, section 1">man(1)</a> for details. Overridden by <code class="Fl">-M</code>, ignored if <code class="Fl">-l</code> is specified.</dd> <dt id="PAGER"><a class="permalink" href="#PAGER"><code class="Ev">PAGER</code></a></dt> <dd>Specifies the pagination program to use when <code class="Ev">MANPAGER</code> is not defined. If neither PAGER nor MANPAGER is defined, <a class="Xr" href="/less.1" aria-label="less, section 1">less(1)</a> is used. Only used if <code class="Fl">-a</code> or <code class="Fl">-l</code> is specified.</dd> </dl> </section> <section class="Sh"> <h2 class="Sh" id="FILES"><a class="permalink" href="#FILES">FILES</a></h2> <dl class="Bl-tag Bl-compact"> <dt><span class="Pa">mandoc.db</span></dt> <dd>name of the <a class="Xr" href="/makewhatis.8" aria-label="makewhatis, section 8">makewhatis(8)</a> keyword database</dd> <dt><span class="Pa">/etc/man.conf</span></dt> <dd>default <a class="Xr" href="/man.1" aria-label="man, section 1">man(1)</a> configuration file</dd> </dl> </section> <section class="Sh"> <h2 class="Sh" id="EXIT_STATUS"><a class="permalink" href="#EXIT_STATUS">EXIT STATUS</a></h2> <p class="Pp">The <code class="Nm">apropos</code> utility exits 0 on success, and >0 if an error occurs.</p> </section> <section class="Sh"> <h2 class="Sh" id="EXAMPLES"><a class="permalink" href="#EXAMPLES">EXAMPLES</a></h2> <p class="Pp">Search for ".cf" as a substring of manual names and descriptions:</p> <p class="Pp"></p> <div class="Bd Bd-indent"><code class="Li">$ apropos =.cf</code></div> <p class="Pp">Include matches for ".cnf" and ".conf" as well:</p> <p class="Pp"></p> <div class="Bd Bd-indent"><code class="Li">$ apropos =.cf =.cnf =.conf</code></div> <p class="Pp">Search in names and descriptions using a case-sensitive regular expression:</p> <p class="Pp"></p> <div class="Bd Bd-indent"><code class="Li">$ apropos '~set.?[ug]id'</code></div> <p class="Pp">Search for all manual pages in a given section:</p> <p class="Pp"></p> <div class="Bd Bd-indent"><code class="Li">$ apropos -s 9 .</code></div> <p class="Pp">Search for manuals in the library section mentioning both the "optind" and the "optarg" variables:</p> <p class="Pp"></p> <div class="Bd Bd-indent"><code class="Li">$ apropos -s 3 Va=optind -a Va=optarg</code></div> <p class="Pp">Do exactly the same as calling <code class="Nm">whatis</code> with the argument "ssh":</p> <p class="Pp"></p> <div class="Bd Bd-indent"><code class="Li">$ apropos -- -i 'Nm~[[:<:]]ssh[[:>:]]'</code></div> <p class="Pp">The following two invocations are equivalent:</p> <p class="Pp"></p> <div class="Bd Bd-indent"><code class="Li">$ apropos -S</code> <var class="Ar">arch</var> <code class="Li">-s</code> <var class="Ar">section expression</var></div> <div class="Bd Pp Bd-indent"><code class="Li">$ apropos $</code> <var class="Ar">expression</var> <code class="Li">$</code> <code class="Li">-a arch~^(</code><var class="Ar">arch</var><code class="Li">|any)$</code> <code class="Li">-a sec~^</code><var class="Ar">section</var><code class="Li">$</code></div> </section> <section class="Sh"> <h2 class="Sh" id="SEE_ALSO"><a class="permalink" href="#SEE_ALSO">SEE ALSO</a></h2> <p class="Pp"><a class="Xr" href="/man.1" aria-label="man, section 1">man(1)</a>, <a class="Xr" href="/re_format.7" aria-label="re_format, section 7">re_format(7)</a>, <a class="Xr" href="/makewhatis.8" aria-label="makewhatis, section 8">makewhatis(8)</a></p> </section> <section class="Sh"> <h2 class="Sh" id="STANDARDS"><a class="permalink" href="#STANDARDS">STANDARDS</a></h2> <p class="Pp">The <code class="Nm">apropos</code> utility is compliant with the <span class="St">IEEE Std 1003.1-2008 (“POSIX.1”)</span> specification of <a class="Xr" href="/man.1" aria-label="man, section 1">man(1)</a> <code class="Fl">-k</code>.</p> <p class="Pp">All options, the <code class="Nm">whatis</code> command, support for logical operators, macro keys, substring matching, sorting of results, the environment variables <code class="Ev">MANPAGER</code> and <code class="Ev">MANPATH</code>, the database format, and the configuration file are extensions to that specification.</p> </section> <section class="Sh"> <h2 class="Sh" id="HISTORY"><a class="permalink" href="#HISTORY">HISTORY</a></h2> <p class="Pp">Part of the functionality of <code class="Nm">whatis</code> was already provided by the former <code class="Nm">manwhere</code> utility in <span class="Ux">1BSD</span>. The <code class="Nm">apropos</code> and <code class="Nm">whatis</code> utilities first appeared in <span class="Ux">2BSD</span>. They were rewritten from scratch for <span class="Ux">OpenBSD 5.6</span>.</p> <p class="Pp">The <code class="Fl">-M</code> option and the <code class="Ev">MANPATH</code> variable first appeared in <span class="Ux">4.3BSD</span>; <code class="Fl">-m</code> in <span class="Ux">4.3BSD-Reno</span>; <code class="Fl">-C</code> in <span class="Ux">4.4BSD-Lite1</span>; and <code class="Fl">-S</code> and <code class="Fl">-s</code> in <span class="Ux">OpenBSD 4.5</span> for <code class="Nm">apropos</code> and in <span class="Ux">OpenBSD 5.6</span> for <code class="Nm">whatis</code>. The options <code class="Fl">-acfhIKklOTWw</code> appeared in <span class="Ux">OpenBSD 5.7</span>.</p> </section> <section class="Sh"> <h2 class="Sh" id="AUTHORS"><a class="permalink" href="#AUTHORS">AUTHORS</a></h2> <p class="Pp"><span class="An">Bill Joy</span> wrote <code class="Nm">manwhere</code> in 1977 and the original <span class="Ux">BSD</span> <code class="Nm">apropos</code> and <code class="Nm">whatis</code> in February 1979. The current version was written by <span class="An">Kristaps Dzonsons</span> <<a class="Mt" href="mailto:kristaps@bsd.lv">kristaps@bsd.lv</a>> and <span class="An">Ingo Schwarze</span> <<a class="Mt" href="mailto:schwarze@openbsd.org">schwarze@openbsd.org</a>>.</p> </section> </main> <div class="foot" role="doc-pagefooter" aria-label="Manual footer line"><span class="foot-left"></span><span class="foot-date">October 1, 2020</span> <span class="foot-os">OpenBSD-current</span></div> </body> </html>