How is pthread_self() implemented?

[Will Bryant]

> John Bossom's original design also allows for pre-existing Win32 threads
> to use any POSIX routines, and therefore fully interact with POSIX
> threads, by creating a one-time-only on-the-fly detached POSIX thread
> handle for the Win32 thread.

So it is safe to use all pthreads-win32 functions from threads not created
using the pthreads interface?  I have an application where nearly all of the
code only needs to use standard windows threads, but there are a couple of
condition variables that I'd like to be able to use...