bpm_read_tbt_buffer_lock_c

	status.i4.v = bpm_read_tbt_buffer_lock_c(house.ch.d, max_return.i4.v,
						 locked.i4a.r,
						 num_returned.i4.r)

	This routine returns the status of the BPM turn by turn
	data buffer lock.

	house		ASCII house name (If a value of NULL is passed for
			this argument, all buffer locks for the present
			machine will be read.)
	max_return	maximum number of values to return
	locked		returned turn by turn data buffer lock status
			(TRUE -> turn by turn buffer is locked,
			 FALSE -> turn by turn buffer is not locked)
	num_returned	returned number of status values returned

	This function returns ACNET status values as follows:

	OK			success
	CBS_NOTYET		not supported for the currently selected
				machine
	CBS_INVARG		invalid house name
	otherwise		other ACNET error

	This function requires the following include files:

	ul_cbsaux/bpmuti.h, cnsparam_h, acnet_errors_h

	Related functions:

	bpm_machine_c, bpm_lock_tbt_buffer_c, bpm_set_global_tbt_timing_c,
	bpm_set_tbt_timing_c, bpm_get_tbt_timing_c, bpm_get_global_tbt_timing_c,
	bpm_enable_tbt_trigger_c, bpm_is_tbt_trigger_enabled

	C/C++ usage:

	static const char	house[] = "A1";
	int	status;
	int	max_return = MAX_RETURN;
	int	locked[MAX_RETURN];
	int	num_returned;

	status = bpm_read_tbt_buffer_lock_c(house,max_return,locked,
					    &num_returned);