VMS Help DCE_THREADS, Thread Intro, Thread Cancellation Routines  *Conan The Librarian (sorry for the slow response - running on an old VAX)

   pthread_cancel            Allows a thread to request that it, or
                             another thread, terminate execution.

   pthread_cleanup_pop       Removes a cleanup handler routine from the
                             top of the cleanup stack and optionally
                             executes it.

   pthread_cleanup_push      Establishes a cleanup handler routine to
                             be executed when the thread exits or is
                             canceled.

   pthread_setcancelstate    Sets the current thread's cancelability
                             state.

   pthread_setcanceltype     Sets the current thread's cancelability
                             type.

   pthread_testcancel        Requests delivery of any pending
                             cancelation request to the current thread.