Chris Marcellino <cmarcellino(at)apple(dot)com> writes:
> I searched through the archives and I can't find a mention of why the
> posix_sema code was written for Darwin.
Because Darwin didn't have anything else at the time.
> If this is in fact the case, I have a trivial patch to conditionally
> enable SysV semaphores based on the OS release:
Outta curiosity, can you measure any performance difference?
regards, tom lane