filename	IN:	Name of the file
	rank	IN:	Number of dimensions
	dimsizes	IN:	Dimensions of the data buffer
	data	OUT:	Buffer for the data

	Purpose	Reads the next dataset in the file.
	Return value	Returns SUCCEED (or 0) if successful and FAIL (or -1) otherwise.
	Description	If the values of rank or dimsizes aren't known, DFSDgetdims must be called to retrieve them and then use them to determine the buffer space needed for the array data. If the data type of the data in a scientific dataset isn't know, DFSDgetNT must be called to retrieve it. Subsequent calls to DFSDgetdata (or to DFSDgetdims and DFSDgetdata)will sequentially read scientific datasets from the file. For example, if DFSDgetdata is called three times in succession, the third call reads data from the third scientific dataset in the file.
		If DFSDgetdims or DFSDgetdata is called and there are no more scientific datasets left in the file, an error code is returned and nothing is read. DFSDrestart can be used to override this convention.

	FORTRAN	integer function dsgdata(filename, rank, dimsizes, data)
		character*(*) filename
		integer rank
		integer dimsizes(*), data(*)