APROPOS(1) Manual pager utils APROPOS(1)
apropos - search the manual page names and descriptions
apropos [-dalv?V] [-e|-w|-r] [-s list] [-m system[,...]] [-M path] [-L
locale] [-C file] keyword ...
Each manual page has a short description available within it. apropos
searches the descriptions for instances of keyword.
keyword is usually a regular expression, as if (-r) was used, or may
contain wildcards (-w), or match the exact keyword (-e). Using these
options, it may be necessary to quote the keyword or escape (\) the
special characters to stop the shell from interpreting them.
The standard matching rules allow matches to be made against the page
name and word boundaries in the description.
The database searched by apropos is updated by the mandb program.
Depending on your installation, this may be run by a periodic cron job,
or may need to be run manually after new manual pages have been
Print debugging information.
Print verbose warning messages.
Interpret each keyword as a regular expression. This is the
default behaviour. Each keyword will be matched against the
page names and the descriptions independently. It can match any
part of either. The match is not limited to word boundaries.
Interpret each keyword as a pattern containing shell style wild-
cards. Each keyword will be matched against the page names and
the descriptions independently. If --exact is also used, a
match will only be found if an expanded keyword matches an
entire description or page name. Otherwise the keyword is also
allowed to match on word boundaries in the description.
Each keyword will be exactly matched against the page names and
Only display items that match all the supplied keywords. The
default is to display items that match any keyword.
Do not trim output to the terminal width. Normally, output will
be truncated to the terminal width to avoid ugly results from
poorly-written NAME sections.
-s list, --sections list, --section list
Search only the given manual sections. list is a colon- or
comma-separated list of sections. If an entry in list is a sim-
ple section, for example "3", then the displayed list of
descriptions will include pages in sections "3", "3perl", "3x",
and so on; while if an entry in list has an extension, for exam-
ple "3perl", then the list will only include pages in that exact
part of the manual section.
-m system[,...], --systems=system[,...]
If this system has access to other operating system's manual
page descriptions, they can be searched using this option. To
search NewOS's manual page descriptions, use the option -m
The system specified can be a combination of comma-delimited
operating system names. To include a search of the native oper-
ating system's whatis descriptions, include the system name man
in the argument string. This option will override the $SYSTEM
-M path, --manpath=path
Specify an alternate set of colon-delimited manual page hierar-
chies to search. By default, apropos uses the $MANPATH environ-
ment variable, unless it is empty or unset, in which case it
will determine an appropriate manpath based on your $PATH envi-
ronment variable. This option overrides the contents of $MAN-
-L locale, --locale=locale
apropos will normally determine your current locale by a call to
the C function setlocale(3) which interrogates various environ-
ment variables, possibly including $LC_MESSAGES and $LANG. To
temporarily override the determined value, use this option to
supply a locale string directly to apropos. Note that it will
not take effect until the search for pages actually begins.
Output such as the help message will always be displayed in the
initially determined locale.
-C file, --config-file=file
Use this user configuration file rather than the default of
Print a help message and exit.
Print a short usage message and exit.
Display version information.
0 Successful program execution.
1 Usage, syntax or configuration file error.
2 Operational error.
16 Nothing was found that matched the criteria specified.
SYSTEM If $SYSTEM is set, it will have the same effect as if it had
been specified as the argument to the -m option.
If $MANPATH is set, its value is interpreted as the colon-delim-
ited manual page hierarchy search path to use.
If $MANWIDTH is set, its value is used as the terminal width
(see the --long option). If it is not set, the terminal width
will be calculated using the value of $COLUMNS, an ioctl(2) if
available, or falling back to 80 characters if all else fails.
If $POSIXLY_CORRECT is set, even to a null value, the default
apropos search will be as an extended regex (-r). Nowadays,
this is the default behaviour anyway.
A traditional global index database cache.
An FHS compliant global index database cache.
A traditional whatis text database.
man(1), whatis(1), mandb(8)
Fabrizio Polacco (firstname.lastname@example.org).
Colin Watson (email@example.com).
220.127.116.11 2016-12-12 APROPOS(1)