status.i4.v = dio_default_data_event_c(device_indices.i4a.r,
					       errors.i2a.r, num_devices.i4.v)

	This routine returns the default data event string for a device
	and property (DI/PI).  If "num_devices" is specified, default
	data events for a list of devices/properties can be retrieved.

	device_indices	device index or array of device indices
	properties	property index or array of indices
			(If the first value is less than zero, all devices
			 will be requested with a property index which is
			 equal to the absolute value of this argument.)
			(constants are in 'dbprops')
	data_events	returned null terminated default data event string or
			array of data event strings
			(DATA_EVENT_MAX_LEN + 1 characters per entry)
			(A value of NULL can be passed for this argument if
			 only caching of the data event information is desired.)
	errors		returned ACNET status value or array of status values
	num_devices	number of devices

	This function returns status values as follows:

	OK			success
	DIO_BADARG		invalid number of devices passed
	DIO_MEMFAIL		memory allocation failure
	negative value		ACNET format error indicating overall failure
	positive value		number of devices in error indicating partial

	This function requires the following include files:

	dbprops_h, diolib_h, acnet_errors_h

	Related functions:

	dio_longest_default_data_event, dio_default_ftd, dio_get_raw(_c),
	dio_get_dev(_c), dio_dpreq_info, dio_cache_property_info_c,

	C/C++ usage:

	char	data_events[NUM_DEVICES][DATA_EVENT_MAX_LEN];
	short	errors[NUM_DEVICES];
	short	properties = -PRREAD;
	int	status;
	static const int	device_indices[NUM_DEVICES] = {14430, 14431};
	int	num_devices = NUM_DEVICES;

	status = dio_default_data_event_c(device_indices,&properties,