1    /ENCODING

       /ENCODING=type

    This qualifier controls the type of decoding used to decode the
    input file. The possible values for this qualifier are BASE64,
    CBASE64 (gzip compressed BASE64), BASE85, BINHEX (encoding only,
    not the file format), BTOA, HEXADECIMAL, PATHWORKS, QUOTED_
    PRINTABLE, UUENCODE, CUUENCODE (gzip compressed UUENCODE). If the
    /HEADER qualifier is specified, then it should not be necessary
    to specify the encoding used as this should be given in the
    message header. The /ENCODING qualifier will override the header
    specification if it is used.

2    /FILENAME

       /FILENAME
       /NOFILENAME (default)

    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. The default
    is /NOFILENAME in which case any file name specified in the
    Content-type: header line is ignored.

3    /HEADER

       /HEADER
       /NOHEADER (default)

    This qualifier controls whether or not the encoded file begins
    with a MIME-compliant header. /NOHEADER is the default. When
    /NOHEADER is used, the /ENCODING qualifier is usually needed
    to specify the encoding since it cannot be determined from the
    header. To decode material that begins with a MIME-compliant
    header, e.g., specifying the encoding used, use the /HEADER
    qualifier.