rfc753.txt

RFC 的详细文档！

    Reasons

      These could be mailbox does not exist, mailbox full, etc.

      LIST ( TEXT )

    Stamp

      Each MPM that handles the message must add a unique identifier
      (ihn, see above) to the list.  This will prevent messages from
      being sent back and forth through the internet mail system without
      eventually either being delivered or returned to the sender.

      LIST ( ihn, ihn, ... )

    Trail

      When a message is sent through the internetwork environment, it
      acquires a list of MPMs that have handled the message in "Stamp".
      This list is then carried as "Trail" upon reply or acknowledgment
      of that message. More simply, requests and replies always have a
      "Stamp" and each MPM adds its ihn to this "Stamp."  Replies, in
      addition, have a "Trail" which is the complete "Stamp" of the
      original message.

      LIST ( ihn, ihn, ... )

    Type

      The command type, e.g., request or reply.

      INDEX

  Document

    In this section, we define some objects useful in message document
    headers.  The ones we use are taken from the current ARPANET message
    syntax standard [6,8].

    CC

      When copies of a message are sent to others in addition to the
      addresses in the To object, those to whom the copies are sent will
      have their addresses recorded here.  CC will be a single TEXT
      element.

      TEXT



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                                               Internet Message Protocol
                                                           Specification



    Date

      The date and time are represented according to the International
      Standards Organization (ISO) recommendations [13,14,15].  Taken
      together the ISO recommendations 2014, 3307, and 4031 result in
      the following representation of the date and time:

        yyyy-mm-dd-hh:mm:ss,fff+hh:mm

      Where yyyy is the 4 digit year, mm is the two digit month, dd is
      the two digit day, hh is the two digit hour in 24 hour time, mm is
      the two digit minute, ss is the two digit second, and fff is the
      decimal fraction of the second.  To this basic date and time is
      appended the offset from Greenwich as plus or minus hh hours and
      mm minutes.

      TEXT

    Document-Body

      The document body will contain that portion of the message
      commonly thought of as the text portion.  It will be composed of a
      list of elements.  This will allow transmission of data other than
      pure text if such capabilities are needed.  We can, for instance,
      envision digital voice communication through the transmission of
      BITSTR element, or transmission of graphic data, etc.  Information
      regarding control of such features could be included in the header
      for cooperating sites, or in the body itself but such protocols
      would depend upon agreement among those sites involved.  It is
      expected of course that the majority of messages will contain body
      portions comprised of TEXT elements.

      LIST ( --- )

    Document-Header

      The document header contains the memo header presented to the
      user.  In principle this may be of any style or structure.  In
      this specification it is recommended that a PROPLIST be used and
      that the name-value pairs correspond to the header fields of
      RFC 733 [6].

      PROPLIST ( --- )







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    From

      The From is meant to be the name of the author of a document.  It
      will be one TEXT element.

      TEXT

    Reply-To

      Sometimes it will be desired to direct the replies of a message to
      some address other than the From or the Sender.  In such a case
      the Reply-To object can be used.

      TEXT

    Sender

      The Sender will contain the address of the individual who sent the
      message. In some cases this is NOT the same as the author of the
      message. Under such a condition, the author should be specified in
      the From object.  The Sender is a single TEXT element.

      TEXT

    Subject

      The subject of the message.

      TEXT

    To

      To identifies the addressees of the message.  The To object is one
      TEXT element.

      TEXT














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                                               Internet Message Protocol
                                                           Specification



3.4.  Command

  This section describes the commands which processes in the internet
  message system can use to communicate.  Several aspects of the command
  structure are based on the NSW Transaction Protocol [19].  The
  commands come in pairs, with each request having a corresponding
  reply.

   A command is a list:

    LIST ( mailbox, stamp, type, operation, arguments, error-list )

  The arguments are described generally here and more specifically, if
  necessary, in the description of each command.

    mailbox:  PROPLIST

      This is the "to" specification of the message.  Mailbox takes the
      form of a property list of general information, some of which is
      the essential information for delivery, and some of which could be
      extra information which may be helpful for delivery.  Mailbox is
      different from address in that address is a very specific list
      without extra information.

    stamp:  LIST ( INTEGER, ...  )

      This is a list of the MPMs that have handled the message.  Each
      MPM must add its 32 bit Internet Host Number (ihn) to the LIST.

    type: INDEX

      type=1 a REQUEST operation.

      type=2 a REPLY operation.

      type=3 an ALARM operation. (A high priority message.)

      type=4 a RESPONSE to an alarm operation.

    operation: TEXT

      Operation is the name of the operation or procedure to be
      performed.  This string must be interpreted in an upper/lower case
      independent manner.






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    arguments: LIST

      This is a list of arguments to the above operation.

    error-list:  LIST

      If message is type 1 or 3 (a request or an alarm):

        LIST ( )  (a zero length list)

      If message is a type 2 or 4 (a response or response to alarm)

        LIST ( error-class, error-string ) indicates what,if any, error
        occured

      error-class: INDEX

        =0: indicates success, no error
        =1: partial results returned.
          This error class is used when several steps are performed by
          one operation and some of them fail.
        =2: failure, resources unavailable.
        =3: failure, user error.
        =4: failure, MPM error. Recoverable.
        =5: failure, MPM error. Fatal.
        =6: User abort requested

      error-string: TEXT

        This is a human readable character string describing the error.

    Possible errors:

              error-string                  error-class

      No errors                                  0
      Command not implemented                    2
      Syntax error, command unrecognized         3
      Syntax error, in arguments                 3
      Server error, try again later              4
      No service available                       5
      User requested abort                       6








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                                               Internet Message Protocol
                                                           Specification



  command:  DELIVER

    type:  1

    function:  Sends message to a mailbox

    reply:  The reply is ACKNOWLEDGE

    arguments:  LIST ( options )

      options:  one or more of the following

        "REGULAR"  regular delivery

        "FORWARD"  message forwarding

        "GENDEL"   general delivery

        other options which may be defined later

    argument structure:

      LIST ( LIST ( TEXT, ... ))



























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  command:  ACKNOWLEDGE

    type:  2

    function:  reply to DELIVER

    arguments: LIST ( tid, trail, answer, reasons, how-delivered )

      tid:  tid of the originating message

      trail:   the stamp from the deliver command

      answer:  yes if delivered successfully,
               no if error in delivery.

      reasons:  if the answer is yes, the reason is "ok", if the answer
      is no the reason could be one of "no such user", "no such host",
      "no such network", "address ambiguous", or a similar response

      how-delivered:  one or more of the following:

        "FORWARD"  message was accepted for forwarding

        "GENDEL"   message was accepted for general delivery

        "ACCEPT"   message was accepted for normal delivery

        other types of delivery may be defined later

    argument structure:

      LIST ( LIST ( INDEX, INTEGER ),
             LIST ( INTEGER, ...  ),
             BOOLEAN,
             LIST ( TEXT ),
             LIST ( TEXT ))














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                                               Internet Message Protocol
                                                           Specification



  command:  PROBE

    type:  1

    function:  finds out if specified mailbox (specified in mailbox of
    the command) exists at a host

    reply:  the reply is RESPONSE

    arguments:  LIST ( --none-- )

    argument structure:

      LIST ( )




































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  command:  RESPONSE

    type:  2

    function:  reply to PROBE

    arguments:  LIST ( tid, trail, answer, address OR reasons )

      tid:  the tid which came from the originating PROBE

      trail:  the stamp which came from the originating PROBE

      answer:  Yes if mailbox found, or no for invalid mailbox