Atomic Task and Set Operations

[chris_edgar]

Hi,

On a single CPU machine ++*sem and --*sem (sem being a pointer to an int or long depending on the OS) are "atomic" but on a multi-cpu machine they appear not to be.

On Apple, SCO, Windows, and AIX all have an atomic function to do this.

In Windows the function is : InterlockedExchange(sem,1) which if *sem is zero it puts a 1 in and returns 0 ...

In SC the function is qxchgl( sem, 1 ) and works the same as windows.

I am looking for a linux implementaion of the above. Please can any one help?

Regards,

Chris

[wje_lf]

Do this at the command line:

less /usr/include/asm/atomic.h

Hope this helps.