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APROPOS(1)                 OpenBSD Reference Manual                 APROPOS(1)

     apropos - search manual page databases

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

     The apropos utility queries manual page databases generated by
     makewhatis(8), evaluating expression for each file in each database.  By
     default, it displays 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.

     Its arguments are as follows:

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

     -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.

     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 by manual sections and names, with output 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

     MANPATH  The standard search path used by man(1) may be changed by
              specifying a path in the MANPATH environment variable.  Invalid
              paths, or paths without manual databases, are ignored.
              Overridden by -M.  If MANPATH begins with a colon, it is
              appended to the default list; if it ends with a colon, it is
              prepended to the default list; or if it contains two adjacent
              colons, the standard search path is inserted between the colons.
              If none of these conditions are met, it overrides the standard
              search path.

     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(1) 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)

     An apropos utility first appeared in 2BSD.  It was 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.

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

OpenBSD 5.4                     April 18, 2014                     OpenBSD 5.4