Event Operations:

    int Create_Event()

	    Purpose  : Allocates an event.
	    Args     : Nothing.
	    Returns  : Event identification if successful;
		       -1 if not successful.


    int Advance(int event)

	    Purpose  : Advances a given event counter.
	    Args     : event - event for which to advance.
	    Returns  : 0  if successful.
      		       -1 if not successful.


    int Read_Count(int event)

	    Purpose  : Gives the count of an event.
	    Args     : event - specified event.
	    Returns  : Current local count of the event.
      		       -1 if not successful.


    int Await(int event,
	      int count)

	    Purpose  : Waits for an event to reach a specified count.
	    In       : event - specified event.
      		       count - event count specification on which to unblock.
	    Out      : Nothing.
	    Returns  : New count of the event.
      		       -1 if not successful.


    int Await_with_Timeout(int event,
                           int count,
                           struct timeval *timeout)

	    Purpose  : Waits for an event to reach a specified count or
                       until timeout expires.
	    In       : event - specified event.
      		       count - event count specification on which to unblock.
                       timeout - maximum time to wait.
	    Out      : Nothing.
	    Returns  : New count of the event (could be less than specified
                       count).
      		       -1 if not successful.


Sequencer Operations:

    int Create_Sequencer(int seq_type)

	    Purpose : Allocates a sequencer.
            Args    : seq_type - sequencer type: one of
				  - SEQUENTIAL_TICKETS,
                                  - RANDOM_TICKETS.
	    Args    : Nothing.
	    Returns : Allocated sequencer id;
		      -1 on error.


    int Destroy_Sequencer(int sequencer)

	    Purpose : Deallocates a sequencer.
	    Args    : Sequencer id to deallocate;
	    Returns : 0 on success.
		      -1 on error.


    int Get_Ticket(int sequencer)

	    Purpose : Obtains a ticket.
	    Args    : sequencer - specifed sequencer.
	    Returns : Allocated ticket on success (> 0);
		      -1 on error.
