logger_return_data

	status.i4.v = logger_return_data(request_reply.s.r)
    	
	This routine returns logged data from a specific lumberjack.

	request_reply	request and reply data
			(structure of type LOGGER_DATA)

			typedef struct LOGGER_DATA
			    {
			    short 	tc_or_status;
			    short 	num_devices;
			    short 	num_points;
			    short 	min_delta_time;
			    unsigned int	start_time;
			    unsigned int	stop_time;
			    unsigned int	first_time;
			    char	device_names[5][LOGGER_SHORT_DEVICE_NAME_LEN];
			    unsigned int	data[1];
			    } LOGGER_DATA;

	Since a time retrieval window may result in the return of thousands of
	points, repetitive calls to logger_return_data are made to return all
	the data.  The user initializes the "request_reply" structure once to
	begin the retrieval and thereafter provides the structure as a seed to
	continue the retrieval.  The request typecode should have a value of
	LOGGER_REQUEST_DATA, the number of devices may be 1-5, the total
	structure size should not exceed ACNET_PACKET_SIZE bytes, and the start
	and stop times are specified in the form of the C language time()
	routine (seconds since January 1, 1970).  The caller will be returned
	the number of found points and alternating timestamp and data
	beginning at "data".  If the returned count is less than requested, the
	structure may be reused without modification to collect another
	portion of data within the specified time window.  The user should note
	that the timestamps have a resolution of one second though the
	datalogger is capable of logging data as fast as 15 times per second.
	This implies that duplicate timestamps may be returned.  If the user
	has specified more than one device for retrieval, the logger assumes
	that only time correlated values are of interest.  The logger discards
	any data point whose timestamp/data does not exist for all devices.
	If a single device is requested, the returned data consists of
	repeating integer timestamps and floating point readings beginning at
	the address of "->data[0]".  Likewise, if multiple devices are
	requested, the returned data consists of repeating unsigned integer
	timestamps and an array of floating point values.  The best example
	of how to use this routine is found in the source code for the
	Lumberjack plotter application (D44).  The field "min_delta_time"
	is the number of seconds of minimum time separation between points.
	This should normally be zero.  The archiver uses this field to
	compress data returns.

	This function returns ACNET status values as follows:

	OK			success
	LJ_INVLEN		invalid number of points requested
	LJ_INVTC		invalid type code
	LJ_MEMFAIL		dynamic memory allocation failure
	ACNET_xxx		error in communicating with Lumberjack

	This function requires the following include files:

	cnsparam_h, cns_data_structs_h, clib_h, acnet_errors_h

	Related functions:

	logger_get_device_c, logger_get_device_by_name_c,
	logger_get_device_list_c, logger_setnode, logger_return_names,
	logger_check_alive, logger_restart_lists, logger_shutdown,
	logger_find_device_c

	C/C++ usage:

	int	status;
	LOGGER_DATA	request_reply;

	status = logger_return_data(&request_reply);