{
    "content": [
        {
            "type": "text",
            "text": "# whatis(1) (man)\n\n**Summary:** whatis - display one-line manual page descriptions\n\n**Synopsis:** whatis [-dlv?V] [-r|-w] [-s list] [-m system[,...]] [-M path] [-L locale] [-C file] name ...\n\n## Flags\n\n| Flag | Long | Arg | Description |\n|------|------|-----|-------------|\n| -d | --debug | — | Print debugging information. |\n| -v | --verbose | — | Print verbose warning messages. |\n| -r | --regex | — | Interpret each name as a regular expression. If a name matches any part of a page name, a match will be made. This optio |\n| -w | --wildcard | — | Interpret each name as a pattern containing shell style wildcards. For a match to be made, an expanded name must match t |\n| -l | --long | — | Do not trim output to the terminal width. Normally, output will be truncated to the terminal width to avoid ugly results |\n| -s | — | — | Search only the given manual sections. list is a colon- or comma-separated list of sections. If an entry in list is a si |\n| -m | — | — | If this system has access to other operating systems' manual page names, they can be accessed using this option. To sear |\n| -M | — | — | Specify an alternate set of colon-delimited manual page hierarchies to search. By de‐ fault, whatis uses the $MANPATH en |\n| -L | — | — | whatis will normally determine your current locale by a call to the C function setlo‐‐ cale(3) which interrogates variou |\n| -C | — | — | Use this user configuration file rather than the default of ~/.manpath. -?, --help Print a help message and exit. |\n| — | --usage | — | Print a short usage message and exit. |\n| -V | --version | — | Display version information. |\n\n## See Also\n\n- apropos(1)\n- man(1)\n- mandb(8)\n\n## Section Outline\n\n- **NAME** (2 lines)\n- **SYNOPSIS** (2 lines)\n- **DESCRIPTION** (16 lines)\n- **OPTIONS** (1 lines) — 12 subsections\n  - -d --debug (2 lines)\n  - -v --verbose (2 lines)\n  - -r --regex (4 lines)\n  - -w --wildcard (4 lines)\n  - -l --long (3 lines)\n  - -s --sections= --section= (6 lines)\n  - -m --systems= (9 lines)\n  - -M --manpath= (5 lines)\n  - -L --locale= (7 lines)\n  - -C --config-file= (5 lines)\n  - --usage (2 lines)\n  - -V --version (2 lines)\n- **EXIT STATUS** (8 lines)\n- **ENVIRONMENT** (15 lines)\n- **FILES** (9 lines)\n- **SEE ALSO** (2 lines)\n- **AUTHOR** (4 lines)\n- **BUGS** (6 lines)\n\n## Full Content\n\n### NAME\n\nwhatis - display one-line manual page descriptions\n\n### SYNOPSIS\n\nwhatis [-dlv?V] [-r|-w] [-s list] [-m system[,...]] [-M path] [-L locale] [-C file] name ...\n\n### DESCRIPTION\n\nEach  manual  page  has  a short description available within it.  whatis searches the manual\npage names and displays the manual page descriptions of any name matched.\n\nname may contain wildcards (-w) or be a regular expression (-r).  Using these options, it may\nbe  necessary  to  quote the name or escape (\\) the special characters to stop the shell from\ninterpreting them.\n\nindex databases are used during the search, and are updated by the mandb program.   Depending\non  your installation, this may be run by a periodic cron job, or may need to be run manually\nafter new manual pages have been installed.  To produce an old  style  text  whatis  database\nfrom the relative index database, issue the command:\n\nwhatis -M manpath -w '*' | sort > manpath/whatis\n\nwhere manpath is a manual page hierarchy such as /usr/man.\n\n### OPTIONS\n\n#### -d --debug\n\nPrint debugging information.\n\n#### -v --verbose\n\nPrint verbose warning messages.\n\n#### -r --regex\n\nInterpret  each  name  as  a regular expression.  If a name matches any part of a page\nname, a match will be made.  This option causes whatis to be somewhat  slower  due  to\nthe nature of database searches.\n\n#### -w --wildcard\n\nInterpret  each name as a pattern containing shell style wildcards.  For a match to be\nmade, an expanded name must match the entire page name.  This option causes whatis  to\nbe somewhat slower due to the nature of database searches.\n\n#### -l --long\n\nDo  not  trim output to the terminal width.  Normally, output will be truncated to the\nterminal width to avoid ugly results from poorly-written NAME sections.\n\n#### -s --sections= --section=\n\nSearch only the given manual sections.  list is a colon- or  comma-separated  list  of\nsections.   If  an  entry  in list is a simple section, for example \"3\", then the dis‐\nplayed list of descriptions will include pages in sections \"3\", \"3perl\", \"3x\", and  so\non;  while  if  an  entry in list has an extension, for example \"3perl\", then the list\nwill only include pages in that exact part of the manual section.\n\n#### -m --systems=\n\nIf this system has access to other operating systems' manual page names, they  can  be\naccessed  using  this  option.  To search NewOS's manual page names, use the option -m\nNewOS.\n\nThe system specified can be a combination of comma delimited operating  system  names.\nTo  include  a  search of the native operating system's manual page names, include the\nsystem name man in the argument string.  This option will override the  $SYSTEM  envi‐\nronment variable.\n\n#### -M --manpath=\n\nSpecify an alternate set of colon-delimited manual page hierarchies to search.  By de‐\nfault, whatis uses the $MANPATH environment variable, unless it is empty or unset,  in\nwhich  case  it  will determine an appropriate manpath based on your $PATH environment\nvariable.  This option overrides the contents of $MANPATH.\n\n#### -L --locale=\n\nwhatis will normally determine your current locale by a call to the C function  setlo‐‐\ncale(3)  which interrogates various environment variables, possibly including $LCMES‐‐\nSAGES and $LANG.  To temporarily override the determined value,  use  this  option  to\nsupply  a  locale  string directly to whatis.  Note that it will not take effect until\nthe search for pages actually begins.  Output such as the help message will always  be\ndisplayed in the initially determined locale.\n\n#### -C --config-file=\n\nUse this user configuration file rather than the default of ~/.manpath.\n\n-?, --help\nPrint a help message and exit.\n\n#### --usage\n\nPrint a short usage message and exit.\n\n#### -V --version\n\nDisplay version information.\n\n### EXIT STATUS\n\n0      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\n### ENVIRONMENT\n\nSYSTEM If $SYSTEM is set, it will have the same effect as if it had been specified as the ar‐\ngument to the -m option.\n\nMANPATH\nIf $MANPATH is set, its value is interpreted as the colon-delimited manual page  hier‐\narchy search path to use.\n\nSee the SEARCH PATH section of manpath(5) for the default behaviour and details of how\nthis environment variable is handled.\n\nMANWIDTH\nIf $MANWIDTH is set, its value is used as the terminal width (see the --long  option).\nIf  it  is not set, the terminal width will be calculated using the value of $COLUMNS,\nand ioctl(2) if available, or falling back to 80 characters if all else fails.\n\n### FILES\n\n/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\n### SEE ALSO\n\napropos(1), man(1), mandb(8)\n\n### AUTHOR\n\nWilf. (G.Wilford@ee.surrey.ac.uk).\nFabrizio Polacco (fpolacco@debian.org).\nColin Watson (cjwatson@debian.org).\n\n### BUGS\n\nhttps://gitlab.com/cjwatson/man-db/-/issues\nhttps://savannah.nongnu.org/bugs/?group=man-db\n\n\n\n2.10.2                                       2022-03-17                                    WHATIS(1)\n\n"
        }
    ],
    "structuredContent": {
        "command": "whatis",
        "section": "1",
        "mode": "man",
        "summary": "whatis - display one-line manual page descriptions",
        "synopsis": "whatis [-dlv?V] [-r|-w] [-s list] [-m system[,...]] [-M path] [-L locale] [-C file] name ...",
        "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 name as a regular expression. If a name matches any part of a page name, a match will be made. This option causes whatis to be somewhat slower due to the nature of database searches."
            },
            {
                "flag": "-w",
                "long": "--wildcard",
                "arg": null,
                "description": "Interpret each name as a pattern containing shell style wildcards. For a match to be made, an expanded name must match the entire page name. This option causes whatis to be somewhat slower due to the nature of database searches."
            },
            {
                "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."
            },
            {
                "flag": "-s",
                "long": null,
                "arg": null,
                "description": "Search only the given manual sections. list is a colon- or comma-separated list of sections. If an entry in list is a simple section, for example \"3\", then the dis‐ played list of descriptions will include pages in sections \"3\", \"3perl\", \"3x\", and so on; while if an entry in list has an extension, for example \"3perl\", then the list will only include pages in that exact part of the manual section."
            },
            {
                "flag": "-m",
                "long": null,
                "arg": null,
                "description": "If this system has access to other operating systems' manual page names, they can be accessed using this option. To search NewOS's manual page names, use the option -m NewOS. The system specified can be a combination of comma delimited operating system names. To include a search of the native operating system's manual page names, include the system name man in the argument string. This option will override the $SYSTEM envi‐ ronment variable."
            },
            {
                "flag": "-M",
                "long": null,
                "arg": null,
                "description": "Specify an alternate set of colon-delimited manual page hierarchies to search. By de‐ fault, whatis uses the $MANPATH environment variable, unless it is empty or unset, in which case it will determine an appropriate manpath based on your $PATH environment variable. This option overrides the contents of $MANPATH."
            },
            {
                "flag": "-L",
                "long": null,
                "arg": null,
                "description": "whatis will normally determine your current locale by a call to the C function setlo‐‐ cale(3) which interrogates various environment variables, possibly including $LCMES‐‐ SAGES and $LANG. To temporarily override the determined value, use this option to supply a locale string directly to whatis. 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."
            },
            {
                "flag": "-C",
                "long": null,
                "arg": null,
                "description": "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": "apropos",
                "section": "1",
                "url": "https://www.chedong.com/phpMan.php/man/apropos/1/json"
            },
            {
                "name": "man",
                "section": "1",
                "url": "https://www.chedong.com/phpMan.php/man/man/1/json"
            },
            {
                "name": "mandb",
                "section": "8",
                "url": "https://www.chedong.com/phpMan.php/man/mandb/8/json"
            }
        ],
        "section_outline": [
            {
                "name": "NAME",
                "lines": 2,
                "subsections": []
            },
            {
                "name": "SYNOPSIS",
                "lines": 2,
                "subsections": []
            },
            {
                "name": "DESCRIPTION",
                "lines": 16,
                "subsections": []
            },
            {
                "name": "OPTIONS",
                "lines": 1,
                "subsections": [
                    {
                        "name": "-d --debug",
                        "lines": 2,
                        "flag": "-d",
                        "long": "--debug"
                    },
                    {
                        "name": "-v --verbose",
                        "lines": 2,
                        "flag": "-v",
                        "long": "--verbose"
                    },
                    {
                        "name": "-r --regex",
                        "lines": 4,
                        "flag": "-r",
                        "long": "--regex"
                    },
                    {
                        "name": "-w --wildcard",
                        "lines": 4,
                        "flag": "-w",
                        "long": "--wildcard"
                    },
                    {
                        "name": "-l --long",
                        "lines": 3,
                        "flag": "-l",
                        "long": "--long"
                    },
                    {
                        "name": "-s --sections= --section=",
                        "lines": 6,
                        "flag": "-s"
                    },
                    {
                        "name": "-m --systems=",
                        "lines": 9,
                        "flag": "-m"
                    },
                    {
                        "name": "-M --manpath=",
                        "lines": 5,
                        "flag": "-M"
                    },
                    {
                        "name": "-L --locale=",
                        "lines": 7,
                        "flag": "-L"
                    },
                    {
                        "name": "-C --config-file=",
                        "lines": 5,
                        "flag": "-C"
                    },
                    {
                        "name": "--usage",
                        "lines": 2,
                        "long": "--usage"
                    },
                    {
                        "name": "-V --version",
                        "lines": 2,
                        "flag": "-V",
                        "long": "--version"
                    }
                ]
            },
            {
                "name": "EXIT STATUS",
                "lines": 8,
                "subsections": []
            },
            {
                "name": "ENVIRONMENT",
                "lines": 15,
                "subsections": []
            },
            {
                "name": "FILES",
                "lines": 9,
                "subsections": []
            },
            {
                "name": "SEE ALSO",
                "lines": 2,
                "subsections": []
            },
            {
                "name": "AUTHOR",
                "lines": 4,
                "subsections": []
            },
            {
                "name": "BUGS",
                "lines": 6,
                "subsections": []
            }
        ]
    }
}