1APROPOS(1)                    Manual pager utils                    APROPOS(1)
2
3
4

NAME

6       apropos - search the manual page names and descriptions
7

SYNOPSIS

9       apropos  [-dalv?V] [-e|-w|-r] [-s list] [-m system[,...]] [-M path] [-L
10       locale] [-C file] keyword ...
11

DESCRIPTION

13       Each manual page has a short description available within it.   apropos
14       searches the descriptions for instances of keyword.
15
16       keyword  is  usually  a regular expression, as if (-r) was used, or may
17       contain wildcards (-w), or match the exact keyword (-e).   Using  these
18       options,  it  may  be  necessary to quote the keyword or escape (\) the
19       special characters to stop the shell from interpreting them.
20
21       The standard matching rules allow matches to be made against  the  page
22       name and word boundaries in the description.
23
24       The  database searched by apropos is updated by the mandb program.  De‐
25       pending on your installation, this may be run by a periodic  cron  job,
26       or  may  need  to  be run manually after new manual pages have been in‐
27       stalled.
28

OPTIONS

30       -d, --debug
31              Print debugging information.
32
33       -v, --verbose
34              Print verbose warning messages.
35
36       -r, --regex
37              Interpret each keyword as a regular expression.  This is the de‐
38              fault  behaviour.  Each keyword will be matched against the page
39              names and the descriptions independently.  It can match any part
40              of either.  The match is not limited to word boundaries.
41
42       -w, --wildcard
43              Interpret each keyword as a pattern containing shell style wild‐
44              cards.  Each keyword will be matched against the page names  and
45              the  descriptions  independently.   If  --exact  is also used, a
46              match will only be found if an expanded keyword matches  an  en‐
47              tire  description  or  page name.  Otherwise the keyword is also
48              allowed to match on word boundaries in the description.
49
50       -e, --exact
51              Each keyword will be exactly matched against the page names  and
52              the descriptions.
53
54       -a, --and
55              Only  display  items  that match all the supplied keywords.  The
56              default is to display items that match any keyword.
57
58       -l, --long
59              Do not trim output to the terminal width.  Normally, output will
60              be  truncated  to  the terminal width to avoid ugly results from
61              poorly-written NAME sections.
62
63       -s list, --sections=list, --section=list
64              Search only the given manual sections.   list  is  a  colon-  or
65              comma-separated list of sections.  If an entry in list is a sim‐
66              ple section, for example "3", then the  displayed  list  of  de‐
67              scriptions  will  include  pages in sections "3", "3perl", "3x",
68              and so on; while if an entry in list has an extension, for exam‐
69              ple "3perl", then the list will only include pages in that exact
70              part of the manual section.
71
72       -m system[,...], --systems=system[,...]
73              If this system has access to  other  operating  systems'  manual
74              page  descriptions,  they can be searched using this option.  To
75              search NewOS's manual  page  descriptions,  use  the  option  -m
76              NewOS.
77
78              The system specified can be a combination of comma-delimited op‐
79              erating system names.  To include a search of the native operat‐
80              ing system's whatis descriptions, include the system name man in
81              the argument string.  This option will override the $SYSTEM  en‐
82              vironment variable.
83
84       -M path, --manpath=path
85              Specify  an alternate set of colon-delimited manual page hierar‐
86              chies to search.  By default, apropos uses the $MANPATH environ‐
87              ment  variable,  unless  it  is empty or unset, in which case it
88              will determine an appropriate manpath based on your $PATH  envi‐
89              ronment  variable.   This option overrides the contents of $MAN‐
90              PATH.
91
92       -L locale, --locale=locale
93              apropos will normally determine your current locale by a call to
94              the  C function setlocale(3) which interrogates various environ‐
95              ment variables, possibly including $LC_MESSAGES and  $LANG.   To
96              temporarily  override  the  determined value, use this option to
97              supply a locale string directly to apropos.  Note that  it  will
98              not  take  effect  until  the  search for pages actually begins.
99              Output such as the help message will always be displayed in  the
100              initially determined locale.
101
102       -C file, --config-file=file
103              Use  this  user  configuration  file  rather than the default of
104              ~/.manpath.
105
106       -?, --help
107              Print a help message and exit.
108
109       --usage
110              Print a short usage message and exit.
111
112       -V, --version
113              Display version information.
114

EXIT STATUS

116       0      Successful program execution.
117
118       1      Usage, syntax or configuration file error.
119
120       2      Operational error.
121
122       16     Nothing was found that matched the criteria specified.
123

ENVIRONMENT

125       SYSTEM If $SYSTEM is set, it will have the same effect  as  if  it  had
126              been specified as the argument to the -m option.
127
128       MANPATH
129              If $MANPATH is set, its value is interpreted as the colon-delim‐
130              ited manual page hierarchy search path to use.
131
132              See the SEARCH PATH section of manpath(5) for the default behav‐
133              iour and details of how this environment variable is handled.
134
135       MANWIDTH
136              If  $MANWIDTH  is  set,  its value is used as the terminal width
137              (see the --long option).  If it is not set, the  terminal  width
138              will  be calculated using the value of $COLUMNS, and ioctl(2) if
139              available, or falling back to 80 characters if all else fails.
140
141       POSIXLY_CORRECT
142              If $POSIXLY_CORRECT is set, even to a null  value,  the  default
143              apropos  search  will  be  as an extended regex (-r).  Nowadays,
144              this is the default behaviour anyway.
145

FILES

147       /usr/share/man/index.(bt|db|dir|pag)
148              A traditional global index database cache.
149
150       /var/cache/man/index.(bt|db|dir|pag)
151              An FHS compliant global index database cache.
152
153       /usr/share/man/.../whatis
154              A traditional whatis text database.
155

SEE ALSO

157       man(1), whatis(1), mandb(8)
158

AUTHOR

160       Wilf. (G.Wilford@ee.surrey.ac.uk).
161       Fabrizio Polacco (fpolacco@debian.org).
162       Colin Watson (cjwatson@debian.org).
163

BUGS

165       https://gitlab.com/man-db/man-db/-/issues
166       https://savannah.nongnu.org/bugs/?group=man-db
167
168
169
1702.11.2                            2023-01-08                        APROPOS(1)
Impressum