NAME
apropos
, whatis
— search manual page
databases
SYNOPSIS
apropos |
[-afk ] [-C
file] [-M
path] [-m
path] [-O
outkey] [-S
arch] [-s
section] expression ... |
DESCRIPTION
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 expression 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 less(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
apropos
. -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 case-sensitive extended regular expression. -i
term- If term is a regular expression, it is evaluated case-insensitively. Has no effect on substring terms.
Results are sorted first according to the section number in ascending numerical order, then by the page name in ascending ascii(7) alphabetical order, case-insensitive.
Each output line is formatted as
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
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 include:
ENVIRONMENT
MANPAGER
- Any non-empty value of the environment variable
MANPAGER
is used instead of the standard pagination program, less(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, less(1) is used. Only used if-a
or-l
is specified.
FILES
- mandoc.db
- name of the makewhatis(8) keyword database
- /etc/man.conf
- default man(1) configuration file
EXIT STATUS
The apropos
utility exits 0 on
success, and >0 if an error occurs.
EXAMPLES
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 case-sensitive regular expression:
$ apropos '~set.?[ug]id'
Search for all manual pages in a given section:
$ apropos -s 9 .
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$
SEE ALSO
STANDARDS
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.
HISTORY
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.
AUTHORS
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>.