NAME

     overchan - update the news overview database

SYNOPSIS

     overchan [ -D dir ] [ -c ] [ file... ]

DESCRIPTION

     Overchan reads article data from files or standard input  if
     none  are  specified.  (A single dash in the file list means
     to read standard input.)  It uses this information to update
     the news overview database.  Overchan is designed to be used
     by InterNetNews or the C News ``mkov''  packages  to  update
     the database as the articles come in.  The database for each
     newsgroup is stored in a file named .overview in a newsgroup
     directory within the overview database tree.

     Overchan locks the database file (by  locking  an  auxiliary
     file)  before  appending  the new data.  To purge data after
     articles have been expired, see expireover(8).

     By default, overchan processes its input as an INN  overview
     stream  written  as a ``WO'' entry in the newsfeeds(5) file,
     for example:

          overview:*:Tc,WO:/usr/local/news/bin/overchan

     This data consists of a line of  text,  separated  into  two
     parts  by  a  tab.  The first part is a list of all relative
     pathnames where the article has been written, with a  single
     space  between  entries.   The second part is the data to be
     written into the overview  file,  except  that  the  initial
     article  number  is omitted.  The data in the overview files
     should be expired by running expireover(8).   This  is  nor-
     mally   done  by  adding  the  ``expireover''  flag  to  the
     news.daily(8) invocation.

OPTIONS

     -c   To process the output of the mkov(8) program,  use  the
          ``-c''  flag.   This format is described in the ``nov''
          distribution.

     -D   The ``-D'' flag can be used to specify where the  data-
          bases   are   stored.    The   default   directory   is
          /news/over.view.

HISTORY

     Written by Rob Robertson <rob@violet.berkeley.edu> and  Rich
     $alz  <rsalz@uunet.uu.net>  for InterNetNews.  This is revi-
     sion 1.9, dated 1996/10/29.

SEE ALSO

     expireover(8), news.daily(8), newsfeeds(5), newsoverview(5),
     newsoverview(8).