encoded-file-spec

    Specifies the name of an encoded input file. The input file must
    be a file previously created with the ENCODE utility.

 output-file-spec

    The name of the file to produce as output. The file output by
    DECODE will have the identical format, structure, contents, etc.
    of the original file encoded with ENCODE.

    When the /FILENAME qualifier is used, the output-file-spec is
    treated as a default file specification and as much as possible
    of the file name, if any, specified in the Content-type: header
    line is used to generate the actual output file name.