APROPOS(1)                  General Commands Manual                 APROPOS(1)


     apropos, whatis - search manual page databases


     apropos [-afk] [-C file] [-M path] [-m path] [-O outkey] [-S arch]
             [-s section] expression ...


     The apropos and whatis utilities query manual page databases generated by
     makewhatis(8), evaluating expression for each file in each database.  By
     default, they display the names, section numbers, and description lines
     of all matching manuals.

     By default, apropos searches for makewhatis(8) databases in the default
     paths stipulated by man(1) and uses case-insensitive substring matching
     (the = operator) over manual names and descriptions (the Nm and Nd macro
     keys).  Multiple terms imply pairwise -o.

     whatis is a synonym for apropos -f.

     The options are as follows:

     -a      Instead of showing only the title lines, show the complete manual
             pages, just like man(1) -a would.  If the standard output is a
             terminal device and -c is not specified, use more(1) to paginate
             them.  In -a mode, the options -IKOTW described in the mandoc(1)
             manual are also available.

     -C file
             Specify an alternative configuration file in man.conf(5) format.

     -f      Search for all words in expression 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.

     -k      Support the full expression syntax.  It is the default for

     -M path
             Use the colon-separated path instead of the default list of paths
             searched for makewhatis(8) databases.  Invalid paths, or paths
             without manual databases, are ignored.

     -m path
             Prepend the colon-separated paths to the list of paths searched
             for makewhatis(8) databases.  Invalid paths, or paths without
             manual databases, are ignored.

     -O outkey
             Show the values associated with the key outkey instead of the
             manual descriptions.

     -S arch
             Restrict the search to pages for the specified machine(1)
             architecture.  arch is case insensitive.  By default, pages for
             all architectures are shown.

     -s section
             Restrict the search to the specified section of the manual.  By
             default, pages from all sections are shown.  See man(1) for a
             listing of sections.

     The options -chlw are also supported and are documented in man(1).  The
     options -fkl are mutually exclusive and override each other.

     An expression consists of search terms joined by logical operators -a
     (and) and -o (or).  The -a operator has precedence over -o and both are
     evaluated left-to-right.

     ( expr )
             True if the subexpression expr is true.

     expr1 -a expr2
             True if both expr1 and expr2 are true (logical `and').

     expr1 [-o] expr2
             True if expr1 and/or expr2 evaluate to true (logical `or').

     term    True if term is satisfied.  This has syntax
             [[key[,key...]](=|~)]val, where key is an mdoc(7) macro to query
             and val is its value.  See Macro Keys for a list of available
             keys.  Operator = evaluates a substring, while ~ evaluates a
             regular expression.

     -i term
             If term is a regular expression, it is evaluated case-
             insensitively.  Has no effect on substring terms.

     Results are sorted according to the following criteria:

     1.   The manpath directory tree the page is found in, according to the
          order specified with -M, -m, the MANPATH environment variable, the
          man.conf(5) configuration file, or the default documented in

     2.   The section number in ascending numerical order.

     3.   The page name in ascending ascii(7) alphabetical order, case-

     Each output line is formatted as

           name[, name...](sec) - description

     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

           name(sec/arch) - description

     Resulting manuals may be accessed as

           $ man -s sec name

     If an architecture is specified in the output, use

           $ man -s sec -S arch name

   Macro Keys
     Queries evaluate over a subset of mdoc(7) macros indexed by
     makewhatis(8).  In addition to the macro keys listed below, the special
     key any may be used to match any available macro key.

     Names and description:
           Nm      manual name
           Nd      one-line manual description
           arch    machine architecture (case-insensitive)
           sec     manual section number

     Sections and cross references:
           Sh      section header (excluding standard sections)
           Ss      subsection header
           Xr      cross reference to another manual page
           Rs      bibliographic reference

     Semantic markup for command line utilities:
           Fl      command line options (flags)
           Cm      command modifier
           Ar      command argument
           Ic      internal or interactive command
           Ev      environmental variable
           Pa      file system path

     Semantic markup for function libraries:
           Lb      function library name
           In      include file
           Ft      function return type
           Fn      function name
           Fa      function argument type and name
           Vt      variable type
           Va      variable name
           Dv      defined variable or preprocessor constant
           Er      error constant
           Ev      environmental variable

     Various semantic markup:
           An      author name
           Lk      hyperlink
           Mt      "mailto" hyperlink
           Cd      kernel configuration declaration
           Ms      mathematical symbol
           Tn      tradename

     Physical markup:
           Em      italic font or underline
           Sy      boldface font
           Li      typewriter font

     Text production:
           St      reference to a standards document
           At      AT&T UNIX version reference
           Bx      BSD version reference
           Bsx     BSD/OS version reference
           Nx      NetBSD version reference
           Fx      FreeBSD version reference
           Ox      OpenBSD version reference
           Dx      DragonFly version reference

     In general, macro keys are supposed to yield complete results without
     expecting the user to consider actual macro usage.  For example, results

        Fa   function arguments appearing on Fn lines
        Fn   fuction names marked up with Fo macros
        In   include file names marked up with Fd macros
        Vt   types appearing as function return types and
             types appearing in function arguments in the SYNOPSIS


     MANPAGER  Any non-empty value of the environment variable MANPAGER is
               used instead of the standard pagination program, more(1); see
               man(1) for details.  Only used if -a or -l is specified.

     MANPATH   A colon-separated list of directories to search for manual
               pages; see man(1) for details.  Overridden by -M, ignored if -l
               is specified.

     PAGER     Specifies the pagination program to use when MANPAGER is not
               defined.  If neither PAGER nor MANPAGER is defined, more(1) -s
               is used.  Only used if -a or -l is specified.


     mandoc.db      name of the makewhatis(8) keyword database
     /etc/man.conf  default man(1) configuration file


     The apropos utility exits 0 on success, and >0 if an error occurs.


     Search for ".cf" as a substring of manual names and descriptions:

           $ apropos .cf

     Include matches for ".cnf" and ".conf" as well:

           $ apropos .cf .cnf .conf

     Search in names and descriptions using a regular expression:

           $ apropos '~set.?[ug]id'

     Search for manuals in the library section mentioning both the "optind"
     and the "optarg" variables:

           $ apropos -s 3 Va=optind -a Va=optarg

     Do exactly the same as calling whatis with the argument "ssh":

           $ apropos -- -i 'Nm~[[:<:]]ssh[[:>:]]'

     The following two invocations are equivalent:

           $ apropos -S arch -s section expression

           $ apropos \( expression \) -a arch~^(arch|any)$ -a sec~^section$


     man(1), re_format(7), makewhatis(8)


     Part of the functionality of whatis was already provided by the former
     manwhere utility in 1BSD.  The apropos and whatis utilities first
     appeared in 2BSD.  They were rewritten from scratch for OpenBSD 5.6.

     The -M option and the MANPATH variable first appeared in 4.3BSD; -m in
     4.3BSD-Reno; -C in 4.4BSD-Lite1; and -S and -s in OpenBSD 4.5 for apropos
     and in OpenBSD 5.6 for whatis.  The options -acfhIKklOTWw appeared in
     OpenBSD 5.7.


     Bill Joy wrote manwhere in 1977 and the original BSD apropos and whatis
     in February 1979.  The current version was written by Kristaps Dzonsons
     <kristaps@bsd.lv> and Ingo Schwarze <schwarze@openbsd.org>.

OpenBSD 6.4                    February 23, 2018                   OpenBSD 6.4

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