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If you'd like a more helpful answer, consider this:<br />
<br />
The OS [Assuming a Win32 platform] has support for everything you mention.<br />
<br />
Shared memory between applications can be implemented via memory-mapped files. &nbsp;The APIs you need are CreateFileMapping() and MapViewOfFile().<br />
<br />
You will also need two locks - a read lock and a write lock (so you can have multiple readers but only one writer). &nbsp;You can use semaphores for that. &nbsp;The APIs you need are CreateSemaphore(), OpenSemaphore(), WaitForSingleObject() and WaitForMultipleObjects().<br />
<br />
Note that in order to be used between processes, all your objects will need to be &quot;named&quot;.<br />

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If you'd like a more helpful answer, consider this:

The OS [Assuming a Win32 platform] has support for everything you mention.

Shared memory between applications can be implemented via memory-mapped files.  The APIs you need are CreateFileMapping() and MapViewOfFile().

You will also need two locks - a read lock and a write lock (so you can have multiple readers but only one writer).  You can use semaphores for that.  The APIs you need are CreateSemaphore(), OpenSemaphore(), WaitForSingleObject() and WaitForMultipleObjects().

Note that in order to be used between processes, all your objects will need to be "named".


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Hey, pchaloux, you there???<br />

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I'm not using Win32. &nbsp;I'm on MQX, witch is similar to QNX, but on a Motorola platform.<br />
<br />

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I'm not using Win32.  I'm on MQX, witch is similar to QNX, but on a Motorola platform.



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I want to have a region that can be read by many applications at the same time, but only one application at the time can write. &nbsp;There can be no read during a write. &nbsp;There can be many read at once.<br />
Maybe with mutex or semaphore components...<br />
<br />
Thanks in advance.
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I want to have a region that can be read by many applications at the same time, but only one application at the time can write.  There can be no read during a write.  There can be many read at once.
Maybe with mutex or semaphore components...

Thanks in advance.

Shared memory

C is a general-purpose, imperative computer programming language, supporting structured programming, lexical variable scope and recursion, while a static type system prevents many unintended operations. By design, C provides constructs that map efficiently to typical machine instructions, so it has found lasting use in applications that had formerly been coded in assembly language, including operating systems as well as various application software for computers ranging from supercomputers to embedded systems. It is distinct from C++ (which has its roots in C) and C#, and many later languages have borrowed directly or indirectly from C.