HISTORY(5)
NAME
history - record of current and recently expired Usenet
articles
DESCRIPTION
The file /var/lib/news/history keeps a record of all arti-
cles currently stored in the news system, as well as those
that have been received but since expired. In a typical
production environment, this file will be many megabytes.
The file consists of text lines. Each line corresponds to
one article. The file is normally kept sorted in the
order in which articles are received, although this is not
a requirement. Innd(8) appends a new line each time it
files an article, and expire(8) builds a new version of
the file by removing old articles and purging old entries.
Each line consists of two or three fields separated by a
tab, shown below as \t:
<Message-ID> \t date
<Message-ID> \t date \t files
The Message-ID field is the value of the article's Mes-
sage-ID header, including the angle brackets.
The date field consists of three sub-fields separated by a
tilde. All sub-fields are the text representation of the
number of seconds since the epoch -- i.e., a time_t; see
gettimeofday(2). The first sub-field is the article's
arrival date. If copies of the article are still present
then the second sub-field is either the value of the arti-
cle's Expires header, or a hyphen if no expiration date
was specified. If an article has been expired then the
second sub-field will be a hyphen. The third sub-field is
the value of the article's Date header, recording when the
article was posted.
The files field is a set of entries separated by one or
more spaces. Each entry consists of the name of the news-
group, a slash, and the article number. This field is
empty if the article has been expired.
For example, an article cross-posted to comp.sources.unix
and comp.sources.d that was posted on February 10, 1991
(and received three minutes later), with an expiration
date of May 5, 1991, could have a history line (broken
into two lines for display) like the following:
lt;312@litchi.foo.com \t 666162000~673329600~666162180 \t
comp.sources.unix/1104 comp.sources.d/7056
In addition to the text file, there is a dbz(3z) database
associated with the file that uses the Message-ID field as
a key to determine the offset in the text file where the
associated line begins. For historical reasons, the key
includes the trailing \0 byte (which is not stored in the
text file).
HISTORY
Written by Rich $alz lt;rsalz@uunet.uu.net for InterNet-
News. This is revision 1.12, dated 1996/09/06.
SEE ALSO
dbz(3z) expire(8) innd(8) news-recovery(8).