NAME¶
expire.ctl - control file for Usenet article expiration
DESCRIPTION¶
The file
/etc/news/expire.ctl is the default control file for the
expire(8) program, which reads it at start-up. Blank lines and lines
beginning with a number sign (``#'') are ignored. All other lines should be in
one of two formats.
The first format specifies how long to keep a record of fully-expired articles.
This is useful when a newsfeed intermittently offers older news that is not
kept around very long. (The case of very old news is handled by the ``
-c'' flag of
innd(8).) There should only be one line in this
format, which looks like this:
/remember/:days
Where
days is a floating-point number that specifies the upper limit to
remember a Message-ID, even if the article has already expired. (It does not
affect article expirations.)
Most of the lines in the file will consist of five colon-separated fields, as
follows:
pattern:modflag:keep:default:purge
The
pattern field is a list of
wildmat(3)-style patterns,
separated by commas. This field specifies the newsgroups to which the line is
applied. Note that the file is interpreted in order, so that the last line
that matches will be used. This means that general patterns (like a single
asterisk to set the defaults) should appear before specific group
specifications.
The
modflag field can be used to further limit newsgroups to which the
line applies, and should be chosen from the following set:
M Only moderated groups
U Only unmoderated groups
A All groups
The next three fields are used to determine how long an article should be kept.
Each field should be either a number of days (fractions like ``8.5'' are
allowed) or the word ``never.'' The most common use is to specify the default
value for how long an article should be kept. The first and third fields
—
keep and
purge — specify the boundaries within
which an Expires header will be honored. They are ignored if an article has no
Expires header. The fields are specified in the file as ``lower-bound default
upper-bound,'' and they are explained in this order. Since most articles do
not have explicit expiration dates, however, the second field tends to be the
most important one.
The
keep field specifies how many days an article should be kept before
it will be removed. No article in the newsgroup will be removed if it has been
filed for less then
keep days, regardless of any expiration date. If
this field is the word ``never'' then an article cannot have been kept for
enough days so it will never be expired.
The
default field specifies how long to keep an article if no Expires
header is present. If this field is the word ``never'' then articles without
explicit expiration dates will never be expired.
The
purge field specifies the upper bound on how long an article can be
kept. No article will be kept longer then the number of days specified by this
field. All articles will be removed after then have been kept for
purge
days. If
purge is the word ``never'' then the article will never be
deleted.
It is often useful to honor the expiration headers in articles, especially those
in moderated groups. To do this, set
keep to zero,
default to
whatever value you wish, and
purge to never. To ignore any Expires
header, set all three fields to the same value.
There must be exactly one line with a
pattern of ``*'' and a
modflags of ``A'' — this matches all groups and is used to set
the expiration default. It should be the first expiration line.
For example,
## How long to keep expired history
/remember/:5
## Most things stay for two weeks
*:A:14:14:14
## Believe expiration dates in moderated groups, up to six weeks
*:M:1:30:42
## Keep local stuff for a long time
foo.*:A:30:30:30
HISTORY¶
Written by Rich $alz <rsalz@uunet.uu.net> for InterNetNews. This is
revision 1.15, dated 1996/10/29.
SEE ALSO¶
expire(8),
wildmat(3).