NAME¶
applyfilter - apply filter settings to news spool
SYNOPSIS¶
applyfilter [
-v] ...
newsgroup
DESCRIPTION¶
Leafnode is a USENET package intended for small sites, where there are
few users and little disk space, but where a large number of groups is
desired.
Applyfilter is the program to apply filter settings to your newsspool,
particularly after changes that were not in effect at the time the articles
were downloaded with
fetchnews. Applyfilter is used if you want to
remove postings from your spool matching a certain filter pattern (see FILES
below). If the headers of an article match any of the filtering rules, the
article is being deleted from the newsgroup.
Applyfilter sets its real and effective uid to "news".
OPTIONS¶
- -v
- Be verbose.
- newsgroup
- is the newsgroup you want to apply the filter to.
FILES¶
A file specified in the
filterfile option of
/etc/news/leafnode/config contains the set of filtering rules that are
applied to the newsspool. Each rule must be on a separate line. Empty lines
and comments (marked by a # which
MUST be at the beginning of the line)
are allowed and will be ignored.
Each line contains a regular expression that will be compiled with the
PCRE_MULTILINE option set (unless it is a comment line or an empty line).
Every regular expression applied to the whole message header (folded message
headers are unfolded before the match is attempted). If any regular expression
matches the header, the posting gets removed. For example, the following set
of rules will delete all crosspostings to alt.flame.
^Newsgroups:.*[, ]alt.flame$
^Newsgroups:.*[, ]alt.flame,
^Newsgroups: indicates that the pattern should only be applied to the
Newsgroups: header. After the header, an arbitrary number of characters may
follow, ending in either a comma or a space. After that, alt.flame must be in
the line, either at the end of the line (first entry) or in the middle of the
line, followed by other newsgroups (second entry).
Unfortunately, regular expressions are a complex matter and outside the scope of
this document. Please see the manual pages provided with the PCRE library for
details.
Note that some leafnode programs (such as fetchnews) feed the header line
by line to the regexp (after unfolding), others (such as applyfilter) feed the
whole header in one large blob. This does not usually matter because patterns
are compiled in multiline mode, but will matter if you're trying to match
multiple headers in the same regexp -- this would work with applyfilter, but
not with fetchnews.
ENVIRONMENT¶
- LN_LOCK_TIMEOUT
- This variable is parsed as an unsigned integer value and determines how
many seconds applyfilter will wait when trying to obtain the lock file
from another leafnode program. 0 means to wait indefinitely. This variable
takes precedence over the configuration file.
AUTHOR¶
Copyright 1999 by Cornelius Krasel <krasel@wpxx02.toxi.uni-wuerzburg.de>.
Copyright 2002 - 2006 by Matthias Andree <matthias.andree@gmx.de>.
Leafnode was originally written by Arnt Gulbrandsen <agulbra@troll.no> and
is copyright 1995-96 Troll Tech AS, Postboks 6133 Etterstad, 0602 Oslo,
Norway, fax +47 22646949.
SEE ALSO¶
pcrepattern(3),
leafnode(8),
fetchnews(8),
texpire(8).