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

   pthread_getspecific       Obtains the thread-specific data
                             associated with the specified key.

   pthread_key_create        Generates a unique thread-specific data key.

   pthread_setspecific       Sets the thread-specific data value
                             associated with the specified key for the
                             current thread.

   pthread_key_delete        Deletes a thread-specific data key.