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From: bytebug@felix.UUCP (Roger L. Long)
Newsgroups: net.news.sa
Subject: Re: Are there problems if expire runs while news is being received?
Message-ID: <584@felix.UUCP>
Date: Thu, 21-Nov-85 15:21:51 EST
Article-I.D.: felix.584
Posted: Thu Nov 21 15:21:51 1985
Date-Received: Mon, 25-Nov-85 07:23:19 EST
References: <186@pluto.UUCP> <65@calma.UUCP>
Reply-To: bytebug@felix.UUCP (Roger L. Long)
Organization: FileNet Corp., Costa Mesa, CA
Lines: 30

In article <65@calma.UUCP> adams@calma.UUCP (Robert Adams) 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?
>
>Yes, there are problems if expire and the unbatcher run at the
>same time.

>There are other things in the system that look for LCK..BATCHER
>(we feed other sites).  Yes, this has critical region problems
>but, compared to what happens to /usr/lib/news/active when both
>expire and the unbatcher run at the same time, it is a little price.

I've not found that anything nasty happens when running expire at the 
same time we're unbatching news.  I should preface this with the fact
that we are running the 2.10.2 news software.

What happens is that expire doesn't update the active file.  It builds
a new file named "nactive", and then renames nactive to active when it
is finished.  If during the time that expire is running new news comes
in, the current article numbers that get written to nactive by expire
get outdated.  However when news tries to use that article number to
post a new article to, it sees that something is already there and puts
an error message into the error log.  It then increments the article
number and tries again.  Expire does the same sort of thing when
dealing with the history file:  it builds "nhistory" and then renames
it to "history" when it is finished.
-- 
	Roger L. Long
	FileNet Corp
	trwrb!felix!bytebug