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APROPOS(1)		FreeBSD	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 extended regular ex-
     pression matching 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 opera-
	     tors 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) archi-
	     tecture.  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
	     case-sensitive extended regular expression.

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

     Results are sorted	first according	to the section number in ascending nu-
     merical order, then by the	page name in ascending ascii(7)	alphabetical
     order, case-insensitive.

     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 ex-
     pecting the user to consider actual macro usage.  For example, results

	Fa   function arguments	appearing on Fn	lines
	Fn   function 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

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

	   $ apropos =.cnf	=.conf

     Search in names and descriptions using a case-sensitive regular expres-

	   $ 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)

     The apropos utility is compliant with the IEEE Std	1003.1-2008
     ("POSIX.1") specification of man(1) -k.

     All options, the whatis command, support for logical operators, macro
     keys, substring matching, sorting of results, the environment variables
     MANPAGER and MANPATH, the database	format,	and the	configuration file are
     extensions	to that	specification.

     Part of the functionality of whatis was already provided by the former
     manwhere utility in 1BSD.	The apropos and	whatis utilities first ap-
     peared 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
     <> and Ingo	Schwarze <>.

FreeBSD	13.0		       November	22, 2018		  FreeBSD 13.0


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