Description

   This routine wakes one thread waiting on the specified condition
   variable. It can only be called from a software interrupt handler
   routine (such as from a Tru64 UNIX signal handler or OpenVMS
   AST). Calling this routine implies that it might be possible for
   a single waiting thread to proceed.

   The scheduling policies of the waiting threads determine which
   thread is awakened. For policies SCHED_FIFO and SCHED_RR, a
   blocked thread is chosen in priority order, using first-in/first-
   out (FIFO) within priorities.

   This routine does not cause a thread blocked on a condition
   variable to resume execution immediately. A thread resumes
   execution at some time after the interrupt handler routine
   returns. If no threads are waiting on the condition variable
   at the time of the call to pthread_cond_signal_int_np(), the next
   future waiting thread will be automatically released (that is,
   it will not actually wait). This routine establishes a "pending"
   wake if necessary.

   You can call this routine regardless of whether the associated
   mutex is either locked or unlocked. (Never lock a mutex from an
   interrupt handler routine.)

                                  NOTE

      This routine allows you to signal a condition variable from
      a software interrupt handler. Do not call this routine from
      noninterrupt code. To signal a condition variable from the
      normal noninterrupt level, use pthread_cond_signal().