DIFF

        [SIC\]DIFF Var1|File1 Var2|File2

    List  the  differences between two entities. Each entity can be either a
    Sic variable name or a GDF file name  (images,  cubes,  UV  tables,...).
    Comparison is made on their headers (if both variables provide a header)
    and/or their data (if both variables provide a data array).

    The result of the last comparison (true/false) is saved in  the  logical
    variable SIC%DIFF.