Description

   This routine returns the address of the calling thread's own
   thread identifier. For example, you can use this thread object
   to obtain the calling thread's own sequence number. To do so,
   pass the return value from this routine in a call to the pthread_
   getsequence_np() routine, as follows:

      .
      .
      .
      unsigned long     this_thread_nbr;
      .
      .
      .
      this_thread_nbr = pthread_getsequence_np( pthread_self( ) );
      .
      .
      .

   The return value from the pthread_self() routine becomes
   meaningless after the calling thread is destroyed.