$ CONVERT/DOCUMENT /OPTIONS=MY_OPTIONS.CDA$OPTIONS -
    _$ MY_INPUT.DTIF/FORMAT=DTIF MY_OUTPUT.DDIF/FORMAT=DDIF -
    _$ /MESSAGE_FILE=MY_MSGS.MSG

    This command converts an input file named MY_INPUT.DTIF, which
    has the DTIF format, to an output file named MY_OUTPUT.DDIF,
    which has the DDIF format. The specified options file is named
    MY_OPTIONS.CDA$OPTIONS, and the message file is named /MESSAGE_
    FILE=MY_MSGS.MSG.