I agree.  I wrote two little programs.

LOCK.TEST1
0001 LOCK 60 ELSE CRT '60 LOCKED'
0002 CRT 'UNLOCKED'


LOCK.TEST2
0001 UNLOCK 60
0002 CRT '60 WAS UNLOCKED'

LOCK.TEST1 locked 60 displayed "unlocked".
LOCK.TEST2 generated the error ' Program "LOCK.TEST2": Line 1, Lock 60 not 
owned by calling process' and then displayed "60 WAS UNLOCKED".

As I was playing with the test programs as I type this.  it looks like the 
first process needs to perform the first lock.  The second process will then 
lock, and wait on the lock until the first process unlocks.  I need to be able 
to support many-to-one processes.  The "one" process waits on the lock and any 
of the "many" processes need to release the lock... which the old semaphore 
process supported... I confess, I'm spoiled.  :)

Thanks
Tom
-----Original Message-----
From: owner-u2-us...@listserver.u2ug.org 
[mailto:owner-u2-us...@listserver.u2ug.org] On Behalf Of Kevin King
Sent: Thursday, February 26, 2009 2:01 PM
To: u2-users@listserver.u2ug.org
Subject: Re: [U2] Inter-Process Control...

Tom, can you elaborate when you say "the only process that can modify the
lock is the one that set it".  Isn't that exactly how a semaphore is
supposed to work?  Both processes should be able to set the lock but only
one can have it at any moment in time. Or am I missing the point?
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