Re: mutex problems on Windows

[Chris Vine <chris cvine freeserve co uk>]

On Tue, 7 Jul 2009 11:14:02 +0100
Chris Vine <chris cvine freeserve co uk> wrote:

> Richard's approach can be made to work on unix-like OSes (ie those
> where the underlying threading is pthreads) because it respects mutex
> ownership of a locked mutex and the result of double locking a
> non-recursive mutex is defined in pthreads if you choose
> PTHREAD_MUTEX_NORMAL as the mutex type, as deadlocking is mandatory in
> that case, but not otherwise (this is from the POSIX standard):

[snip]

Sorry, scrub that, it's wrong, because this scheme cannot respect mutex
ownership. There is no way you can get the deadlocking thread to unlock
the mutex it is blocking on - it would need to be a different thread,
which is undefined behaviour.

Semaphores or conditional variables it is then.
 
Chris