1APROPOS(1) Manual pager utils APROPOS(1)
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6 apropos - search the manual page names and descriptions
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9 apropos [-dalv?V] [-e|-w|-r] [-s list] [-m system[,...]] [-M path] [-L
10 locale] [-C file] keyword ...
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13 Each manual page has a short description available within it. apropos
14 searches the descriptions for instances of keyword.
15 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 The standard matching rules allow matches to be made against the page
22 name and word boundaries in the description.
23 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
30 -d, --debug
31 Print debugging information.
32 -v, --verbose
34 Print verbose warning messages.
35 -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 -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 -e, --exact
51 Each keyword will be exactly matched against the page names and
52 the descriptions.
53 -a, --and
55 Only display items that match all the supplied keywords. The
56 default is to display items that match any keyword.
57 -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 -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 -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 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 -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 -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 -C file, --config-file=file
103 Use this user configuration file rather than the default of
104 ~/.manpath.
105 -?, --help
107 Print a help message and exit.
108 --usage
110 Print a short usage message and exit.
111 -V, --version
113 Display version information.
114
116 0 Successful program execution.
117 1 Usage, syntax or configuration file error.
119 2 Operational error.
121 16 Nothing was found that matched the criteria specified.
123
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 MANPATH
129 If $MANPATH is set, its value is interpreted as the colon-delim‐
130 ited manual page hierarchy search path to use.
131 See the SEARCH PATH section of manpath(5) for the default behav‐
133 iour and details of how this environment variable is handled.
134 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 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.
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147 /usr/share/man/index.(bt|db|dir|pag)
148 A traditional global index database cache.
149 /var/cache/man/index.(bt|db|dir|pag)
151 An FHS compliant global index database cache.
152 /usr/share/man/.../whatis
154 A traditional whatis text database.
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157 man(1), whatis(1), mandb(8)
158
160 Wilf. (G.Wilford@ee.surrey.ac.uk).
161 Fabrizio Polacco (fpolacco@debian.org).
162 Colin Watson (cjwatson@debian.org).
163
165 https://gitlab.com/cjwatson/man-db/-/issues
166 https://savannah.nongnu.org/bugs/?group=man-db
1672.10.2 2022-03-17 APROPOS(1)