Path: utzoo!mnetor!uunet!husc6!hao!ames!ptsfa!cogent!mark
From: mark@cogent.UUCP (Captain Neptune)
Newsgroups: comp.sys.att
Subject: Re: Shared Memory
Message-ID: <397@cogent.UUCP>
Date: 11 Jan 88 18:23:07 GMT
References: <216@pyuxf.UUCP> <2325@crash.cts.com>
Reply-To: mark@cogent.UUCP (PUT YOUR NAME HERE)
Organization: Cogent Software Solutions, Stockton, CA
Lines: 22

In article <2325@crash.cts.com> ford%kenobi@crash.CTS.COM (Michael Ditto) writes:

>In article <216@pyuxf.UUCP> daveb@pyuxf.UUCP (david berk) writes:
>>Could someone explain how shared memory works...

>Shared memory is primarily useful for interprocess communication.  Several
>programs (or several copies of the same program) can all have access to an
>area of memory...
>
>Other IPC mechanisms include signals, pipes, message queues, and semaphores.

I've been studying IPC lately, and, correct me if I'm wrong, but, I am
led to understand that some sort of locking must be employed to use
shared memory effectively.  Typically, this might be in the form of
semaphores used to insure that only one process at a time updates the
chunk of shared memory.  Reading from the chunk of shared memory might
be less demanding of such restrictions.  Is this correct and on target?
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