MANDB(8)                  (2021-02-08)                   MANDB(8)

          mandb - create or update the manual page index caches

          mandb [-dqsucpt?V] [-C file] [manpath]
          mandb [-dqsut] [-C file] -f filename ...

          mandb is used to initialise or manually update index data-
          base caches.  The caches contain information relevant to the
          current state of the manual page system and the information
          stored within them is used by the man-db utilities to
          enhance their speed and functionality.

          When creating or updating an index, mandb will warn of bad
          ROFF .so requests, bogus manual page filenames and manual
          pages from which the whatis cannot be parsed.

          Supplying mandb with an optional colon-delimited path will
          override the internal system manual page hierarchy search
          path, determined from information found within the man-db
          configuration file.

          mandb can be compiled with support for any one of the fol-
          lowing database types.

          tab (@); l l l.  Name@Async@Filename _ Berkeley
 GNU gdbm@Yes@index.db UNIX

          Those database types that support asynchronous updates pro-
          vide enhanced speed at the cost of possible corruption in
          the event of unusual termination.  In an unusual case where
          this has occurred, it may be necessary to rerun mandb with
          the -c option to re-create the databases from scratch.

          -d, --debug
               Print debugging information.

          -q, --quiet
               Produce no warnings.

          -s, --no-straycats
               Do not spend time looking for or adding information to
               the databases regarding stray cats.

          -p, --no-purge
               Do not spend time checking for deleted manual pages and

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               purging them from the databases.

          -c, --create
               By default, mandb will try to update any previously
               created databases.  If a database does not exist, it
               will create it.  This option forces mandb to delete
               previous databases and re-create them from scratch, and
               implies --no-purge. This may be necessary if a database
               becomes corrupt or if a new database storage scheme is
               introduced in the future.

          -u, --user-db
               Create user databases only, even with write permissions
               necessary to create system databases.

          -t, --test
               Perform correctness checks on manual pages in the hier-
               archy search path.  With this option, mandb will not
               alter existing databases.

          -f, --filename
               Update only the entries for the given filename.  This
               option is not for general use; it is used internally by
               man when it has been compiled with the MAN_DB_UPDATES
               option and finds that a page is out of date.  It
               implies -p and disables -c and -s.

          -C file, --config-file=file
               Use this user configuration file rather than the
               default of ~/.manpath.

          -?, --help
               Show the usage message, then exit.

               Print a short usage message and exit.

          -V, --version
               Show the version, then exit.

          0    Successful program execution.

          1    Usage, syntax, or configuration file error.

          2    Operational error.

          3    A child process failed.

          The following warning messages can be emitted during data-
          base building.

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          <filename>: whatis parse for page(sec) failed
               An attempt to extract whatis line(s) from the given
               <filename> failed.  This is usually due to a poorly
               written manual page, but if many such messages are
               emitted it is likely that the system contains non-
               standard manual pages which are incompatible with the
               man-db whatis parser.  See the WHATIS PARSING section
               in lexgrog(1) for more information.

          <filename>: is a dangling symlink
               <filename> does not exist but is referenced by a sym-
               bolic link.  Further diagnostics are usually emitted to
               identify the <filename> of the offending link.

          <filename>: bad symlink or ROFF `.so'
               <filename> is either a symbolic link to, or contains a
               ROFF include request to, a non existent file.

          <filename>: ignoring bogus filename
               The <filename> may or may not be a valid manual page
               but its name is invalid.  This is usually due to a man-
               ual page with sectional extension <x> being put in man-
               ual page section <y>.

          <filename_mask>: competing extensions
               The wildcard <filename_mask> is not unique.  This is
               usually caused by the existence of both a compressed
               and uncompressed version of the same manual page.  All
               but the most recent are ignored.

               man-db configuration file.

               An FHS compliant global index database cache.

          Older locations for the database cache included:

               A traditional global index database cache.

               An alternate or FSSTND compliant global index database

          lexgrog(1), man(1), manpath(5), catman(8)

          The WHATIS PARSING section formerly in this manual page is
          now part of lexgrog(1).

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          Wilf. (
          Fabrizio Polacco (
          Colin Watson (


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