NAME

     expire.ctl - control file for Usenet article expiration

DESCRIPTION

     The file /usr/local/news/etc/expire.ctl is the default  con-
     trol  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  expira-
     tions.)

     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  inter-
     preted  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 fol-
     lowing 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 boun-
     daries 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  arti-
     cles, 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  expira-
     tion 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).