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From: Jeffrey Carter <spam.jrcarter.not@spam.not.acm.org>
Newsgroups: comp.lang.ada
Subject: Re: can someone help me with this code (explanation)
Date: Thu, 25 Sep 2014 09:53:47 -0700
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Date: 2014-09-25T09:53:47-07:00
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On 09/25/2014 06:44 AM, Stribor40 wrote:
> 
> If we assume John task starts first...first time trough the loop John does
> Gourmet.Make_A_Hot_Dog(Index, TRUE); which blocks him and Goutmet starts
> running so once Gourmet stops John continues does Bill calls Gourmet and John
> wait in the queue in his second loop?

Gourmet, Bill, and John all start at the same time. While Gourmet is printing
its welcome message, Bill and John call Gourmet's entry Make_A_Hot_Dog and are
blocked until Gourmet accepts the entry call. Whichever is first in the entry
queue is largely a matter of chance.

That is how you should think about this. If you have a computer that can run 3
or more tasks at the same time (which describes many modern computers with 2 or
more cores) then it is also what happens. Even on a monoprocessor only able to
run 1 task at a time what will happen will be very close to this, since Gourmet
should block waiting for I/O and the eater tasks should block on the entry call,
so you end up with both eaters in the queue and Gourmet reaching its accept for
the 1st time.

-- 
Jeff Carter
"Blessed is just about anyone with a vested interest in the status quo."
Monty Python's Life of Brian
73