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From: "REH" <spamjunk@stny.rr.com>
Newsgroups: comp.lang.ada
Subject: Re: Simulating OS semaphore behavior
Date: 25 Aug 2006 08:25:13 -0700
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Dmitry A. Kazakov wrote:
> That looks like a classic automatic event for multiple tasks. Make Signal
> an entry:
>
>    protected body Event is
>       entry Wait when Signal'Count > 0 is
>       begin
>          null;
>       end Wait;
>       entry Signal when Wait'Count = 0 is
>       begin
>          null;
>       end Signal;
>    end Event;
>
> Signal is blocked until all waiting tasks get released. There is no race
> condition because fresh attempts to Wait are blocked if a signal is
> pending.
> 

Ah, just what I love: simple and elegant.  Thank you!

REH