Normally, the RMS definition file is automatically modified when you modify the structure of an RMSfile with toolkit or lfedit. You can modify an RMS definition file alone (without restructuring the RMSfile) with the following command:
c:\> filedef deffile
c:\> filedef deffile newdeffile
Lfname is the name of the original RMS definition file. When you exit filedef, the definition is saved in newdeffile (or in deffile if you did not specify newdeffile). See section 4.6, Editing an RMS Definition File for information about entering the definition.