Volatile is Necessary

[Ray Dunn]

In article <77200028 at uiucdcsp> gillies at uiucdcsp.cs.uiuc.edu writes:
>
>C is not a multiprocessor systems programming language.  I'm sorry for
>you multiprocessor programmers.  My advice to you is to buy
>hypercubes, write in assembly language, or develop your own language.
>
>We don't yet understand how to program multiprocessors well, or even
>if shared-memory multiprocessing is the wave of the future.  Please
>don't jump the gun by extending the C language too soon....

Unfortunately, "multiprocessor systems" are more common than you might
think.  We are not necessarily talking about esoteric new architectures when
talking multiprocessor.

As an example, there are many PC option cards, especially comms cards, which
are "intelligent", i.e. have a CPU on board.  These often share memory with
the host CPU, and have software in two parts, an option card part, and a
host part, which communicate via this shared memory.

It would be nice to continue to program these devices in 'C'!

Ray Dunn.  ..{philabs, mnetor)!micomvax!ray