oldbid
The 'oldbid' command is used to invoke the process which
deletes old message-id's (or bids) in the Historyfile. The default
location of Historyfile is /spool/history. Do not confuse this
file with the NNTP History database, stored in /spool/news/history
by default!
oldbid [interval age_in_days]
Begin the oldbid process every <interval> hours, and delete
those bids which are older than <age_in_days> days. If no
arguments are provided, the current oldbid interval and age
are displayed.
Example: To expire bids every 24 hours, that are 30 days
old, use: oldbid 24 30