Description

   PMDF DECODE and ENCODE have been, for the most part, made
   obsolete by PMDF MAIL. If you use PMDF MAIL, then files which
   you send with the SEND command will be encoded automatically,
   if necessary. Encoded messages which you receive will be decoded
   automatically, if necessary, and can simply be extracted to a
   file with the EXTRACT command. If, however, you do not use PMDF
   MAIL, then read on.

   The ENCODE and DECODE utilities are provided with PMDF as a means
   of transmitting OpenVMS binary files via VMS MAIL and other non-
   MIME aware agents. With ENCODE, a file can be encoded in a format
   which uses short records containing only printable characters.
   Such files can then be transmitted through most any mail system
   without being altered (e.g., lines wrapped, characters removed
   or replaced, etc.). ENCODE preserves all file contents and all
   file attributes when encoding a file. The contents and attributes
   are properly restored when decoded with DECODE. Absolutely any
   type of OpenVMS file can be transmitted with these two utilities
   - even indexed files with multiple keys and files with extended
   semantics.

   Encoded files have two parts. The first part is a conventional
   RFC 822 message header. Header lines are used to describe the
   file format; this information includes a conventional OpenVMS
   FDL (file description language) description of the file and
   a description of the encoding used to convert the file into a
   printable form for transfer. ENCODE creates this header; DECODE
   reads it and uses the information it contains to reconstruct the
   file.

                                  NOTE

      Many encoded messages received with PMDF are automatically
      decoded for you, thus obviating the need to use PMDF DECODE
      at all. This is especially true when you use PMDF MAIL whose
      EXTRACT command will extract any MIME encoded message or
      message body part. If you use VMS MAIL, however, you can
      occasionally receive an encoded message which PMDF could not
      deliver in its decoded form to VMS MAIL owing to limitations
      of VMS MAIL itself.