dwww-cache - manage the dwww cache of converted documents
dwww-cache --lookup type location
dwww-cache --store type location
dwww-cache --list type location
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:
If the document is in the cache, output it to the standard
output. Otherwise, output nothing and return a non-zero status.
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 four space
delimited fields: type, pathname of original, pathname of
cached, and permanent flag (y or n).
Like --list, but for all documents.
Forget all cached documents that have been deleted.
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. This
operation removes all entries from the database where either the
original or the converted file is now missing.
To stop the cache from growing too large, an entry in root’s crontab
should remove cached files that have not been accessed for a while.
For example, the following commands remove all documents that have not
been accessed for ten days:
find /var/cache/dwww -atime +10 | xargs rm -f
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.
The cache directory.
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.
Lars Wirzenius <email@example.com>. Modified by Robert Luberda
See dwww(7) for copyrights and stuff.