DWWW-CACHE(8) Debian DWWW-CACHE(8)
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 path-
name of the original document. (See dwww-convert(8) for more informa-
tion about the arguments.)
The operations are:
--lookup
If the document is in the cache, output it to the standard out-
put. 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 stan-
dard output. The information is one line, with five space de-
limited 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either "valid" or "outdated").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Forget all cached documents that are already outdated.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 docu-
ments. 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file is outdated.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 flexibil-
ity. 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@de-
bian.org>.
See dwww(7) for copyrights and stuff.
dwww 1.13.0 February 7th, 2016 DWWW-CACHE(8)
Generated by dwww version 1.14 on Wed Feb 28 00:06:33 CET 2024.