If you have a COBOL copybook that describes a message then you can use the IIB toolkit to import the copybook and create a DFDL message model. The toolkit importer uses default settings when importing a .cpy file, one of which is that a period (.) is the decimal point. If your message uses a comma (,) as the decimal point instead, then you need to include the copybook in a ‘wrapper’ COBOL program and change the decimal point setting using the SPECIAL-NAMES section. Here is an example, assuming the copybook is called ‘COPY1’: Make sure that the copybook and the wrapper program reside in the same directory, and the program has file extension .cbl.
DECIMAL-POINT IS COMMA.
END PROGRAM WRAPPER.
Also works for importing into a message set for MRM.