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From: dmitry@elros.cbb-automation.de (Dmitry A. Kazakov)
Newsgroups: comp.lang.ada
Subject: Re: How to avoid unreferenced objects (mutexes etc)
Date: Tue, 15 Jan 2002 08:53:21 GMT
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On Mon, 14 Jan 2002 18:32:35 -0500, "Matthew Heaney" <mheaney@on2.com>
wrote:

>Yes, a semaphore all by itself is dangerous, because you can forget to
>release it.  But when used in conjuction with a controlled object, the
>release is guaranteed to happen, so there is no danger.

IMO, when it is said that semaphore is a low-level mechanism, it means
approximately the following. Tasks and protected objects may have
entries implementing *something* [useful (:-))]. In contrary to this,
semaphores just implement themselves. A semaphore is useless without
the resource it blocks. But then why is it separated from the
resource?

Regards,
Dmitry Kazakov