Calling sequence


                                    Initialization

Before wgrib2 starts reading data, it calls all the "option functions" with "mode = -1"
which should be used for initialization.

   Some variables that can be set

     decode = 1                     will need the grib file to be decoded


                                      Normal operation


For each grib message (or submessage), all non-init  functions will be called with a 
"mode >= 0".  The mode determines the verbosity index.


                                         Cleanup

Finally all non-init functions will be called with a mode = -2.  This allows routines to 
close files, and do other cleanup tasks.


                                   Calling Arguments

The various functions can have one of the following arguement lists.  ARG0, ARG1 and ARG2 are
the normal argument lists for 0 to 2 optional arguements.  


	int mode = -1 .. setup
		   -2 .. cleanup
                    0 .. valid grid submessage verbose = 0
                    1 .. valid grid submessage verbose = 1
                    2 .. valid grid submessage verbose = 2

	unsigned char **sec = pointer array to all the GRIB sections

	float *data = pointer to the decoded GRIB data (assuming global "decode" = 1)
		      NULL  no data decoded
	int ndata = number of grid points decoded
        char *inv_out = data to be written to standard out