[Python-Dev] semaphore support in thread_*.h

[David Ascher]

I noticed that the support for the semaphore calls in the various thread_*
is very very spotty, with a comment in the BeOS implementation that read:

 * Guido says not to implement this because it's not used anywhere;
 * I'll do it anyway, you never know when it might be handy, and it's
 * easy...

(that last bit is not true of all implementations, apparently =).

1) Is it true that the sema_ calls are never used?

2) If yes, shouldn't we remove the sema_ calls from the thread API and have
similar functionality on all platforms?

(There are related issues re: for example whether async thread locking is
available, whether threads are joinable or not (see thread_cthread.h), etc.)

--david