Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Posting-Version: version B 2.10.2 9/5/84; site daemen.UUCP
Path: utzoo!watmath!sunybcs!daemen!boyce
From: boyce@daemen.UUCP (Doug Boyce)
Newsgroups: net.news
Subject: Re: simulatneous updates to history (?bug)
Message-ID: <762@daemen.UUCP>
Date: Fri, 26-Jul-85 16:43:21 EDT
Article-I.D.: daemen.762
Posted: Fri Jul 26 16:43:21 1985
Date-Received: Sat, 27-Jul-85 03:42:32 EDT
References: <1818@amdahl.UUCP>
Organization: Daemen College, Buffalo, NY
Lines: 31

> If a user is posting an article at the same time the expire
> program is running, isn't there some risk that inews and expire are
> going to update the history database at the same time?  This
> is particularly crucial to the dbm(3) database for history.
> Has anyone examined this problem?  Has anyone implimented a
> file-locking mechanism (portable!) for inews and expire?
> -- 
> Gordon A. Moffett		...!{ihnp4,cbosgd,hplabs}!amdahl!gam

That could probably happen but our feed (sunybcs) took care of that
by writing a doexpire script (which all sites it feeds have).  It creates a
"LOCK" file in the newslib directory so inews/rnews can't add news.  There is
a problem with this though, inews only waits 45 seconds (vanilla 2.10.2) for
the lock to go away so news will be lost.  I increased DEADTIME to be about
40 minutes so if we get news while doexpire is running inews just waits
patiently until it finishes instead dumping the news onto the floor.


-- 

Doug Boyce   Daemen College, Amherst NY

UUCP : {decvax,dual,rocksanne,watmath,rocksvax}!sunybcs!daemen!boyce
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or
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	"What a hypocrite, after all that lecturing about screwing up the
		space-time continuum..."
	"Yeah, well, I figured what the hell.."