NAME¶
history - record of current and recently expired Usenet articles
DESCRIPTION¶
The file
/var/lib/news/history keeps a record of all articles 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 Message-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 article'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 newsgroup, 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:
<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 <rsalz@uunet.uu.net> for InterNetNews. This is
revision 1.12, dated 1996/09/06.
SEE ALSO¶
dbz(3z),
expire(8),
innd(8),
news-recovery(8).