Command_Parameters

file1

   Specifies the first file that is to be compared. If you specify
   /GENERATION for this parameter, file1 must be an element name;
   otherwise, an OpenVMS file specification is assumed.

file2

   Specifies the second file that is to be compared. If you specify
   /GENERATION for this parameter, file2 must be an element name;
   otherwise, an OpenVMS file specification is assumed.

   CMS follows these rules when you do not provide a second file
   specification:

   o  If you direct CMS to take file1 from a location that is not a
      CMS library, CMS uses the next lower file version in the same
      directory as file1.

   o  If you direct CMS to take file1 from a CMS library (by
      specifying /GENERATION), CMS uses the latest default directory
      version of file1 as the second input file.