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From: wls@astrovax.UUCP (William L. Sebok)
Newsgroups: net.news.sa
Subject: Re: Are there problems if expire runs while news is being received?
Message-ID: <687@astrovax.UUCP>
Date: Tue, 19-Nov-85 11:08:54 EST
Article-I.D.: astrovax.687
Posted: Tue Nov 19 11:08:54 1985
Date-Received: Wed, 20-Nov-85 08:23:03 EST
References: <186@pluto.UUCP>
Reply-To: wls@astrovax.UUCP (William L. Sebok)
Organization: Princeton Univ. Astrophysics
Lines: 27

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?

I believe that there may very well be problems. I also very worried about the
history file. I didn't see what I believe to be adequate locking of it in the
source for news 2.10.1 and 2.10.2.

At one time when we were running news 2.10.1 the history dbm files were getting
corrupted (and when they get corrupted the dbm subroutines abort().  The
problem in the end turned out to be hardware but I suspected locking problems.
That was when I inspected the locking code.  I fixed it to my satisfaction
by installing the 4.2 BSD flock() call around the history file accesses.
Installation of the news could be held up by a long expire but to me that
was tolerable.

I haven't gotten around to doing anything like this to news 2.10.2 (and with
news 2.10.3 around the corner I am not likely to get around to it).  Because
of my concerns I run expire here at 8-9 am, after news for the night is shut
off (site princeton and astrovax both run one of Honeyman's recent versions
of Honey Danber that allow different time-of-day restrictions on different
grades, thus allowing news to be confined to night without so restricting
mail).
-- 
Bill Sebok			Princeton University, Astrophysics
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