exited(Term) as
result state for thread_join/2.
If the thread has the attribute
detached(true) it terminates, but its exit status cannot be
retrieved using thread_join/2,
making the value of Term irrelevant. The Prolog stacks and C
thread are reclaimed.
The current implementation is based on the reserved
unwind( exception. This
implies that, unlike the previous implementation that was based on the C
pthread_exit() function, the implementation is safe from the
Prolog point of view. However, it is limited by the semantics of the
unwind exceptions. See section
4.10.1 for details.
thread_exit(Term))
This predicate raises a permission_error if it is known
that the thread cannot handle this case.