Path: utzoo!attcan!uunet!cs.utexas.edu!tut.cis.ohio-state.edu!ucbvax!decwrl!decvax!ima!cfisun!lakart!dg
From: dg@lakart.UUCP (David Goodenough)
Newsgroups: comp.unix.questions
Subject: Re: Summary - How to tell if a process is active
Message-ID: <589@lakart.UUCP>
Date: 23 Jun 89 13:48:15 GMT
References: <763@ctisbv.UUCP>
Organization: Lakart Corporation, Newton, MA
Lines: 32

From article <763@ctisbv.UUCP>, by pim@ctisbv.UUCP (Pim Zandbergen):
] But as our application is mainly turnkey based, I have seen more
] then once that checking the pid only is not enough. Our customers
] turn on the machine, and go right away into the application.
] At that time a resource is being claimed. Then there is a system crash,
] the system is rebooted, and the application is restarteds,
] AND IS RUNNING WITH THE EXACT SAME PID! Hence, when it finds
] the lockfile, it checks for its pid and finds out it exists,
] and fails to claim the resource. The second time the application
] is started it will continue without failure.
] 
] So I am looking for some way to put some extra information into
] the lockfile to find out if the machine has been rebooted
] since the resource claim. What is the most obvious and portable
] way to do this?

Why not just give the lock files a generic name -

/usr/spool/lock/XXresource

or somesuch. Now do a:

rm -f /usr/spool/lock/XX*

in your /etc/rc (or /etc/rc.local if you have a civilized system)
and you're all set: the lockfiles all vanish every time the system
comes up.
-- 
	dg@lakart.UUCP - David Goodenough		+---+
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