VMS Help CONVERT, file, Qualifiers, /FDL  *Conan The Librarian (sorry for the slow response - running on an old VAX)

    Indicates that an FDL file is to be used in creating the output
    file.

    Format

      /FDL=fdl-filespec

    Specifies the FDL file to be used in creating the output file.
    The newly created output file will have the name specified by the
    fdl-filespec command parameter; this name overrides any file name
    specified in the FDL file.

    The default file type for the FDL file is .FDL.