From: Rosen.Adalog@wanadoo.fr (J-P. Rosen)
Subject: Re: Uninterruptible (atomic) operation?
Date: 1996/12/13
Date: 1996-12-13T00:00:00+00:00 [thread overview]
Message-ID: <58r1ed$lem@hetre.wanadoo.fr> (raw)
In-Reply-To: 9612111939.AA14087@most
"W. Wesley Groleau (Wes)" <wwgrol@PSESERV3.FW.HAC.COM> wrote:
>2. An Ada 83 (which I'm stuck with) solution to (1) may not work if
>the reader and the writer are parts of independent Unix processes, and
>the shared object is created by system calls. At first, I thought of
>the solution where the item shared is a pointer to the object, and
>the writer could overwrite the pointer atomically, after non-atomically
>updating/creating a new object. Problem there is that the shared memory
>is guaranteed to be the same address for all processes using it. But
>if it contains a pointer, the object pointed to in process X may be at
>a virtual address that is used for something else by process Y.
IF you are running on a mono-processor, you can have the update
done by a surrogate task that runs at highest priority level.
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| J-P. Rosen | Rosen.Adalog@wanadoo.fr |
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next prev parent reply other threads:[~1996-12-13 0:00 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
1996-12-11 0:00 Uninterruptible (atomic) operation? W. Wesley Groleau (Wes)
1996-12-09 0:00 ` John McCabe
1996-12-13 0:00 ` Robert Dewar
1996-12-12 0:00 ` Robert Dewar
1996-12-13 0:00 ` J-P. Rosen [this message]
1996-12-13 0:00 ` Robert I. Eachus
-- strict thread matches above, loose matches on Subject: below --
1996-12-09 0:00 W. Wesley Groleau (Wes)
1996-12-09 0:00 ` Robert A Duff
1996-12-10 0:00 ` Bob Gilbert
1996-12-11 0:00 ` Robert I. Eachus
1996-12-11 0:00 ` Robert S. White
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