dio_dpreq_info

	status.i4.v = dio_dpreq_info(device_indices.i4a.r, properties.i2a.r,
				     info.spa.r, errors.i2a.r
				     [,num_devices.i4.r])

	This routine returns the necessary database information for making
	a datapool request (DPREQ) call.  If "num_devices" is specified,
	information 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')
	info		pointer to information structure or an array of
			pointers to information structures for a DPREQ call
			(structure(s) of type DBAREQ_INFO)
			(Note: The memory for the actual data structures
			 is allocated by this routine and should NOT be
			 freed by the caller.  The caller should only
			 provide the memory for the pointer(s).)
	errors		returned ACNET status value or array of status values
	[num_devices]	number of devices (default is 1)

	This function returns status values as follows:

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

	This function requires the following include files:

	dbprops_h, cns_data_structs_h, diolib_h, acnet_errors_h

	Related functions:

	dio_cache_property_info_c, dio_request_info_c, dpreq, dio_get_raw(_c),
	dio_get_dev(_c), dio_data_len(_c), dio_default_ftd, dio_node,
	dio_dev_ssdn(_c), dio_protection_mask_c, error_in_list(_c),
	dio_enable_obsolete_dev_info, dio_disable_obsolete_dev_info

	C/C++ usage:

	short		errors[2];
	short		properties = -PRSET;
	int		status;
	static int	device_indices[2] = {14430, 14431};
	int		num_devices = 2;
	DBAREQ_INFO	**info;

	info = (DBAREQ_INFO **) malloc(num_devices*(sizeof(DBAREQ_INFO *)));

	status = dio_dpreq_info(device_indices,&properties,info,errors,
				&num_devices);