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Path: utzoo!watmath!clyde!bonnie!akgua!gatech!seismo!mcvax!ukc!dcl-cs!stephen
From: stephen@dcl-cs.UUCP (Stephen J. Muir)
Newsgroups: net.news.sa
Subject: Re: Are there problems if expire runs while news is being received?
Message-ID: <810@dcl-cs.UUCP>
Date: Fri, 22-Nov-85 23:11:30 EST
Article-I.D.: dcl-cs.810
Posted: Fri Nov 22 23:11:30 1985
Date-Received: Wed, 27-Nov-85 05:29:48 EST
References: <186@pluto.UUCP>
Reply-To: stephen@comp.lancs.ac.uk (Stephen J. Muir)
Organization: Department of Computing at Lancaster University.
Lines: 32
Keywords: murphy

In article <186@pluto.UUCP> warren@pluto.UUCP (Warren Burstein) writes:
>I saw this happening, just wondered if this is a thing to avoid.  Won't
>both programs be updating the active file at the same time?

There are 3 cases to consider here:

1) Highest article number too low:
   When new news is later received for this newsgroup, "rnews" will try to
   create the file with the same name as an existing one, but it will notice
   that it already exists and try the next one instead.  It will keep doing
   this until it manages to get a non-existant file name.  After that, the
   problem will have fixed itself.

2) New newsgroup creation:
   There may indeed be a problem here, but the time window in which this can
   happen is very small.  This is the time "expire" takes to rename the file
   after detecting end-of-file.

3) Newsgroup deletion:
   On our system, this is done manually and I make sure neither "expire" or
   "rnews" is running.

There is a more serious bug (which I have fixed on my system).  Once "expire"
has finished with the history file, it doesn't flush its buffers before
starting its work on the active file.  This gives quite a large time slot in
which "rnews" can corrupt the history file.
-- 
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