bionic (8) dwww-cache.8.gz

Provided by: dwww_1.13.4_amd64 bug

NAME

       dwww-cache - manage the dwww cache of converted documents

SYNOPSIS

       dwww-cache --lookup type location
       dwww-cache --store type location
       dwww-cache --list type location
       dwww-cache --list-all
       dwww-cache --clean

DESCRIPTION

       dwww-cache  manages  the  cache  of  converted  documents;  it  is part of dwww(7).  An option (the first
       argument) specifies the operation.  Some operations operate  on  the  whole  cache,  and  need  no  other
       arguments.   Others  need  the second and third argument to specify the type and pathname of the original
       document.  (See dwww-convert(8) for more information about the arguments.)

       The operations are:

       --lookup
              If the document is in the cache, output it to the standard output.  Otherwise, output nothing  and
              return a non-zero status.

       --store
              Read  the document from the standard input, output it to the standard output and store it into the
              cache.  If there was an older version already in the cache, remove it.

       --list Output information about one document in the cache to the standard output.  The information is one
              line,  with five space delimited fields: type, pathname of original file, pathname of cached file,
              size (actually the last two bytes of size) of the cached file, and cache  entry validity indicator
              (which can be either "valid" or "outdated").

       --list-all
              Like --list, but for all documents.

       --clean
              Forget all cached documents that are already outdated.

       dwww-cache  maintains  a database with information of the cached documents.  The documents themselves are
       stored in separate files in the cache directory.  When old documents are removed  from  the  cache  by  a
       suitable crontab entry, they will still exist in the database.  The --clean operation removes all entries
       from the database where either the original or the converted file is missing or where the converted  file
       is outdated.

       To  stop  the  cache from growing too large, there should be an entry for dwww-refresh-cache(8) in system
       crontab to remove cached files that have not  been  accessed  for  a  while.   The  dwww-refresh-cache(8)
       program internally uses commands similar to
              find /var/cache/dwww -atime +$DWWW_KEEPDAYS | xargs rm -f
              dwww-cache --clean
       to  remove all documents that have not been accessed for a number of days specified in the $DWWW_KEEPDAYS
       configuration variable.

       The idea is to first delete the old cached files and then clean up the database.  The policy of  cleaning
       the  cache  has  been  kept  outside  of  dwww-cache  to  keep  the  program simple, and to allow maximum
       flexibility.  The default dwww installation creates a /etc/cron.daily/dwww,  which  automatically  cleans
       the cache each day.

FILES

       /var/cache/dwww/db
              The cache directory.

       /var/cache/dwww/db/.cache_db
              The  database  with  information  about  all  cached  documents.  This is a binary file, specially
              encoded for small size and high speed, and should not be touched by anyone but dwww-cache.

SEE ALSO

       dwww(7), dwww-convert(8).  dwww-refresh-cache(8).

AUTHOR

       Lars Wirzenius <liw@iki.fi>.  Modified by Robert Luberda <robert@debian.org>.
       See dwww(7) for copyrights and stuff.