How do I synchronize access to shared memory in LynxOS/POSIX?

Posted by GrahamS on Stack Overflow See other posts from Stack Overflow or by GrahamS
Published on 2010-04-06T12:15:19Z Indexed on 2010/04/06 12:33 UTC
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posix

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ipc

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shared-memory

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c

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lynxos

I am implementing two processes on a LynxOS SE (POSIX conformant) system that will communicate via shared memory.

One process will act as a "producer" and the other a "consumer". In a multi-threaded system my approach to this would be to use a mutex and condvar (condition variable) pair, with the consumer waiting on the condvar (with pthread_cond_wait) and the producer signalling it (with pthread_cond_signal) when the shared memory is updated.

How do I achieve this in a multi-process, rather than multi-threaded, architecture?

Is there a LynxOS/POSIX way to create a condvar/mutex pair that can be used between processes?
Or is some other synchronization mechanism more appropriate in this scenario?

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