SHared Memory


Thread Starter

phil wilshire

HI all,
Well I've put something in your CVS tree.
Not much but it is a start.

I do not have the checkout details here I'll post those later today.

What I have done is cut a copy of the RT Linux shared memory system. This will allow a kernel module and a user space module to use the same named section of shared memory.

This will need to be extended to give it read and write semaphores.

Using this system ( and it IS simple to use ) means that you have two things.
1 A Much simpler shared memory structure to get started with
2 A possible RT Linux road block is removed , The door is still open to use it

I'll populate it with some of my generic pointer less structure stuff over the next few days.

This is intended to give us some example code to ponder about rather than speculating the pros and cons of certain directions.

You don't have to use it but at least it is there to look at.

On the timer front we are working on posix timers for RT Linux. This should be a plug in module like the shared memory stuff.

These timers would be , in theory , all you need for your timer work and they would be NT portable ( well at least they will conform to Posix if
that helps )

I am not joining in with much of the general discussions I tend to agree with everything
Rick J says. I will only say that this should be considered as a professional project even if I can't spell. I would hope that the art of debate, as in most of the Open Source community, is used to produce the required product.

Comments welcome.
Phil Wilshire

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Curt Wuollet

Thank you Phil;

Even though I have been working on the same thing, even though Simon has been working on a map, what you have done is extremely valuable due to it's timeliness. We at last have something to focus on and get some people pointed in the same direction. And it comes at a point where it is critical to maintain momentum. I will check it out ASAP and will begin writing a first pass driver interface to it so folks can see how they fit together. Even if they both get thrown away later, their value will have been realized in getting the project going.

Thanks again

Curt Wuollet,
Wide Open Technologies

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