{
    "mode": "info",
    "parameter": "apropos",
    "section": "",
    "url": "https://www.chedong.com/phpMan.php/info/apropos/json",
    "generated": "2026-07-28T00:32:57Z",
    "synopsis": "apropos  [-dalv?V] [-e|-w|-r] [-s list] [-m system[,...]] [-M path] [-L\nlocale] [-C file] keyword ...",
    "sections": {
        "NAME": {
            "content": "apropos - search the manual page names and descriptions\n",
            "subsections": []
        },
        "SYNOPSIS": {
            "content": "apropos  [-dalv?V] [-e|-w|-r] [-s list] [-m system[,...]] [-M path] [-L\nlocale] [-C file] keyword ...\n",
            "subsections": []
        },
        "DESCRIPTION": {
            "content": "Each manual page has a short description available within it.   apropos\nsearches the descriptions for instances of keyword.\n\nkeyword  is  usually  a regular expression, as if (-r) was used, or may\ncontain wildcards (-w), or match the exact keyword (-e).   Using  these\noptions,  it  may  be  necessary to quote the keyword or escape (\\) the\nspecial characters to stop the shell from interpreting them.\n\nThe standard matching rules allow matches to be made against  the  page\nname and word boundaries in the description.\n\nThe  database searched by apropos is updated by the mandb program.  De-\npending on your installation, this may be run by a periodic  cron  job,\nor  may  need  to  be run manually after new manual pages have been in-\nstalled.\n",
            "subsections": []
        },
        "OPTIONS": {
            "content": "",
            "subsections": [
                {
                    "name": "-d, --debug",
                    "content": "Print debugging information.\n",
                    "flag": "-d",
                    "long": "--debug"
                },
                {
                    "name": "-v, --verbose",
                    "content": "Print verbose warning messages.\n",
                    "flag": "-v",
                    "long": "--verbose"
                },
                {
                    "name": "-r, --regex",
                    "content": "Interpret each keyword as a regular expression.  This is the de-\nfault  behaviour.  Each keyword will be matched against the page\nnames and the descriptions independently.  It can match any part\nof either.  The match is not limited to word boundaries.\n",
                    "flag": "-r",
                    "long": "--regex"
                },
                {
                    "name": "-w, --wildcard",
                    "content": "Interpret each keyword as a pattern containing shell style wild-\ncards.  Each keyword will be matched against the page names  and\nthe  descriptions  independently.   If  --exact  is also used, a\nmatch will only be found if an expanded keyword matches  an  en-\ntire  description  or  page name.  Otherwise the keyword is also\nallowed to match on word boundaries in the description.\n",
                    "flag": "-w",
                    "long": "--wildcard"
                },
                {
                    "name": "-e, --exact",
                    "content": "Each keyword will be exactly matched against the page names  and\nthe descriptions.\n",
                    "flag": "-e",
                    "long": "--exact"
                },
                {
                    "name": "-a, --and",
                    "content": "Only  display  items  that match all the supplied keywords.  The\ndefault is to display items that match any keyword.\n",
                    "flag": "-a",
                    "long": "--and"
                },
                {
                    "name": "-l, --long",
                    "content": "Do not trim output to the terminal width.  Normally, output will\nbe  truncated  to  the terminal width to avoid ugly results from\npoorly-written NAME sections.\n\n-s list, --sections=list, --section=list\nSearch only the given manual sections.   list  is  a  colon-  or\ncomma-separated list of sections.  If an entry in list is a sim-\nple section, for example \"3\", then the  displayed  list  of  de-\nscriptions  will  include  pages in sections \"3\", \"3perl\", \"3x\",\nand so on; while if an entry in list has an extension, for exam-\nple \"3perl\", then the list will only include pages in that exact\npart of the manual section.\n\n-m system[,...], --systems=system[,...]\nIf this system has access to  other  operating  systems'  manual\npage  descriptions,  they can be searched using this option.  To\nsearch NewOS's manual  page  descriptions,  use  the  option  -m\nNewOS.\n\nThe system specified can be a combination of comma-delimited op-\nerating system names.  To include a search of the native operat-\ning system's whatis descriptions, include the system name man in\nthe argument string.  This option will override the $SYSTEM  en-\nvironment variable.\n\n-M path, --manpath=path\nSpecify  an alternate set of colon-delimited manual page hierar-\nchies to search.  By default, apropos uses the $MANPATH environ-\nment  variable,  unless  it  is empty or unset, in which case it\nwill determine an appropriate manpath based on your $PATH  envi-\nronment  variable.   This option overrides the contents of $MAN-\nPATH.\n\n-L locale, --locale=locale\napropos will normally determine your current locale by a call to\nthe  C function setlocale(3) which interrogates various environ-\nment variables, possibly including $LCMESSAGES and  $LANG.   To\ntemporarily  override  the  determined value, use this option to\nsupply a locale string directly to apropos.  Note that  it  will\nnot  take  effect  until  the  search for pages actually begins.\nOutput such as the help message will always be displayed in  the\ninitially determined locale.\n\n-C file, --config-file=file\nUse  this  user  configuration  file  rather than the default of\n~/.manpath.\n\n-?, --help\nPrint a help message and exit.\n",
                    "flag": "-l",
                    "long": "--long"
                },
                {
                    "name": "--usage",
                    "content": "Print a short usage message and exit.\n",
                    "long": "--usage"
                },
                {
                    "name": "-V, --version",
                    "content": "Display version information.\n",
                    "flag": "-V",
                    "long": "--version"
                }
            ]
        },
        "EXIT STATUS": {
            "content": "0      Successful program execution.\n\n1      Usage, syntax or configuration file error.\n\n2      Operational error.\n\n16     Nothing was found that matched the criteria specified.\n",
            "subsections": []
        },
        "ENVIRONMENT": {
            "content": "SYSTEM If $SYSTEM is set, it will have the same effect  as  if  it  had\nbeen specified as the argument to the -m option.\n\nMANPATH\nIf $MANPATH is set, its value is interpreted as the colon-delim-\nited manual page hierarchy search path to use.\n\nSee the SEARCH PATH section of manpath(5) for the default behav-\niour and details of how this environment variable is handled.\n\nMANWIDTH\nIf  $MANWIDTH  is  set,  its value is used as the terminal width\n(see the --long option).  If it is not set, the  terminal  width\nwill  be calculated using the value of $COLUMNS, and ioctl(2) if\navailable, or falling back to 80 characters if all else fails.\n\nPOSIXLYCORRECT\nIf $POSIXLYCORRECT is set, even to a null  value,  the  default\napropos  search  will  be  as an extended regex (-r).  Nowadays,\nthis is the default behaviour anyway.\n",
            "subsections": []
        },
        "FILES": {
            "content": "/usr/share/man/index.(bt|db|dir|pag)\nA traditional global index database cache.\n\n/var/cache/man/index.(bt|db|dir|pag)\nAn FHS compliant global index database cache.\n\n/usr/share/man/.../whatis\nA traditional whatis text database.\n",
            "subsections": []
        },
        "SEE ALSO": {
            "content": "man(1), whatis(1), mandb(8)\n",
            "subsections": []
        },
        "AUTHOR": {
            "content": "Wilf. (G.Wilford@ee.surrey.ac.uk).\nFabrizio Polacco (fpolacco@debian.org).\nColin Watson (cjwatson@debian.org).\n",
            "subsections": []
        },
        "BUGS": {
            "content": "https://gitlab.com/cjwatson/man-db/-/issues\nhttps://savannah.nongnu.org/bugs/?group=man-db\n\n2.10.2                            2022-03-17                        APROPOS(1)",
            "subsections": []
        }
    },
    "summary": "apropos - search the manual page names and descriptions",
    "flags": [
        {
            "flag": "-d",
            "long": "--debug",
            "arg": null,
            "description": "Print debugging information."
        },
        {
            "flag": "-v",
            "long": "--verbose",
            "arg": null,
            "description": "Print verbose warning messages."
        },
        {
            "flag": "-r",
            "long": "--regex",
            "arg": null,
            "description": "Interpret each keyword as a regular expression. This is the de- fault 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."
        },
        {
            "flag": "-w",
            "long": "--wildcard",
            "arg": null,
            "description": "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 en- tire description or page name. Otherwise the keyword is also allowed to match on word boundaries in the description."
        },
        {
            "flag": "-e",
            "long": "--exact",
            "arg": null,
            "description": "Each keyword will be exactly matched against the page names and the descriptions."
        },
        {
            "flag": "-a",
            "long": "--and",
            "arg": null,
            "description": "Only display items that match all the supplied keywords. The default is to display items that match any keyword."
        },
        {
            "flag": "-l",
            "long": "--long",
            "arg": null,
            "description": "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 de- scriptions 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 systems' manual page descriptions, they can be searched using this option. To search NewOS's manual page descriptions, use the option -m NewOS. The system specified can be a combination of comma-delimited op- erating system names. To include a search of the native operat- ing system's whatis descriptions, include the system name man in the argument string. This option will override the $SYSTEM en- vironment variable. -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- PATH. -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 $LCMESSAGES 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 ~/.manpath. -?, --help Print a help message and exit."
        },
        {
            "flag": "",
            "long": "--usage",
            "arg": null,
            "description": "Print a short usage message and exit."
        },
        {
            "flag": "-V",
            "long": "--version",
            "arg": null,
            "description": "Display version information."
        }
    ],
    "examples": [],
    "see_also": [
        {
            "name": "man",
            "section": "1",
            "url": "https://www.chedong.com/phpMan.php/man/man/1/json"
        },
        {
            "name": "whatis",
            "section": "1",
            "url": "https://www.chedong.com/phpMan.php/man/whatis/1/json"
        },
        {
            "name": "mandb",
            "section": "8",
            "url": "https://www.chedong.com/phpMan.php/man/mandb/8/json"
        }
    ]
}