rfc1064.txt

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                                   <-- A003 OK Fetch complete
                                       {Wait for command}
       A004 FETCH 8 RFC822.TEXT -->
                                   <-- * 8 Fetch (RFC822.TEXT {893}
                                           ...893 characters of text...
                                   <-- )
                                   <-- A004 OK Fetch complete
                                       {Wait for command}

       A005 STORE 8 +Flags \Deleted -->
                                   <-- * 8 Store (Flags (\Deleted
                                                  \Seen))
                                   <-- A005 OK Store complete
                                       {Wait for command}
       A006 EXPUNGE             -->
                                   <-- * 19 EXISTS
                                   <-- * 8 EXPUNGE
                                   <-- * 18 EXISTS
                                   <-- A006 Expunge complete
                                       {Wait for command}
       A007 LOGOUT              -->
                                   <-- * BYE IMAP2 server quitting
                                   <-- A007 OK Logout complete
       {Close Connection}       --><-- {Close connection}
                                       {Go back to start}



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RFC 1064                         IMAP2                         July 1988


Conventions

   The following terms are used in a meta-sense in the syntax
   specification below:

      An ASCII-STRING is a sequence of arbitrary ASCII characters.

      An ATOM is a sequence of ASCII characters delimited by SP or CRLF.

      A CHARACTER is any ASCII character except """", "{", CR, LF, "%",
      or "\".

      A CRLF is an ASCII carriage-return character followed immediately
      by an ASCII linefeed character.

      A NUMBER is a sequence of the ASCII characters which represent
      decimal numerals ("0" through "9"), delimited by SP, CRLF, ",", or
      ":".

      A SP is the ASCII space character.

      A TEXT_LINE is a human-readable sequence of ASCII characters up to
      but not including a terminating CRLF.

   One of the most common fields in the IMAP2 protocol is a STRING,
   which may be an ATOM, QUOTED-STRING (a sequence of CHARACTERs inside
   double-quotes), or a LITERAL.  A literal consists of an open brace
   ("{"), a number, a close brace ("}"), a CRLF, and then an ASCII-
   STRING of n characters, where n is the value of the number inside the
   brace. In general, a string should be represented as an ATOM or
   QUOTED-STRING if at all possible.  The semantics for QUOTED-STRING or
   LITERAL are checked before those for ATOM; therefore an ATOM used in
   a STRING may only contain CHARACTERs.  Literals are most often sent
   from the server to the client; in the rare case of a client to server
   literal there is a special consideration (see the "+ text" response
   below).

   Another important field is the SEQUENCE, which identifies a set of
   messages by consecutive numbers from 1 to n where n is the number of
   messages in the mailbox.  A sequence may consist of a single number,
   a pair of numbers delimited by colon indicating all numbers between
   those two numbers, or a list of single numbers and/or number pairs.
   For example, the sequence 2,4:7,9,12:15 is equivalent to
   2,4,5,6,7,9,12,13,14,15 and identifies all of those messages.







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RFC 1064                         IMAP2                         July 1988


Definitions of Commands and Responses

     Summary of Commands and Responses

       Commands                            ||      Responses
       --------                            ||      -------
       tag NOOP                            ||      tag OK text
       tag LOGIN user password             ||      tag NO text
       tag LOGOUT                          ||      tag BAD text
       tag SELECT mailbox                  ||      * message_number data
       tag CHECK                           ||      * FLAGS flag_list
       tag EXPUNGE                         ||      * SEARCH sequence
       tag COPY sequence mailbox           ||      * BYE text
       tag FETCH sequence data             ||      * OK text
       tag STORE sequence data value       ||      * NO text
       tag SEARCH search_program           ||      * BAD text
                                           ||      + text

Commands

   tag NOOP

      The NOOP command returns an OK to the client.  By itself, it does
      nothing, but certain things may happen as side effects.  For
      example, server implementations which implicitly check the mailbox
      for new mail may do so as a result of this command.  The primary
      use of this command is to for the client to see if the server is
      still alive (and notify the server that the client is still alive,
      for those servers which have inactivity autologout timers).

   tag LOGIN user password

      The LOGIN command identifies the user to the server and carries
      the password authenticating this user.  This information is used
      by the server to control access to the mailboxes.

      EXAMPLE: A001 LOGIN SMITH SESAME logs in as user SMITH with
      password SESAME.

   tag LOGOUT

      The LOGOUT command indicates the client is done with the session.
      The server sends an unsolicited BYE response before the (tagged)
      OK response, and then closes the connection.

   tag SELECT mailbox

      The SELECT command selects a particular mailbox.  The server must



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RFC 1064                         IMAP2                         July 1988


      check that the user is permitted read access to this mailbox.
      Prior to returning an OK to the client, the server must send an
      unsolicited FLAGS and <n> EXISTS response to the client giving the
      flags list for this mailbox (simply the system flags if this
      mailbox doesn't have any special flags) and the number of messages
      in the mailbox.  It is also recommended that the server send a <n>
      RECENT unsolicited response to the client for the benefit of
      clients which make use of the number of new messages in a mailbox.

      Multiple SELECT commands are permitted in a session, in which case
      the prior mailbox is deselected first.

      The default mailbox for the SELECT command is INBOX, which is a
      special name reserved to mean "the primary mailbox for this user
      on this server".  The format of other mailbox names is operating
      system dependent (as of this writing, it reflects the filename
      path of the mailbox file on the current servers).

      EXAMPLE: A002 SELECT INBOX selects the default mailbox.

   tag CHECK

      The CHECK command forces a check for new messages and a rescan of
      the mailbox for internal change for those implementations which
      allow multiple simultaneous read/write access to the same mailbox
      (e.g., TOPS-20).  It is recommend that periodic implicit checks
      for new mail be done by servers as well.  The server should send
      an unsolicited <n> EXISTS response prior to returning an OK to the
      client.

   tag EXPUNGE

      The EXPUNGE command permanently removes all messages with the
      \DELETED flag set in its flags from the mailbox.  Prior to
      returning an OK to the client, for each message which is removed,
      an unsolicited <n> EXPUNGE response is sent indicating which
      message was removed.  The message number of each subsequent
      message in the mailbox is immediately decremented by 1; this means
      that if the last 5 messages in a 9-message mail file are expunged
      you will receive 5 "* 5 EXPUNGE" responses.  To ensure mailbox
      integrity and server/client synchronization, it is recommended
      that the server do an implicit check prior to commencing the
      expunge and again when the expunge is completed.  Furthermore, if
      the server allows multiple simultaneous access to the same mail
      file the server must lock the mail file for exclusive access while
      an expunge is taking place.





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RFC 1064                         IMAP2                         July 1988


      EXPUNGE is not allowed if the user does not have write access to
      this mailbox.

   tag COPY sequence mailbox

      The COPY command copies the specified message(s) to the specified
      destination mailbox.  If the destination mailbox does not exist,
      the server should create it.  Prior to returning an OK to the
      client, the server should return an unsolicited <n> COPY response
      for each message copied.  A copy should set the \SEEN flag for all
      messages which were successfully copied (provided, of course, that
      the user has write access to this mailbox).

      EXAMPLE: A003 COPY 2:4 MEETING copies messages 2, 3, and 4 to
      mailbox "MEETING".

      COPY is not allowed if the user does not have write access to the
      destination mailbox.

   tag FETCH sequence data

      The FETCH command retrieves data associated with a message in the
      mailbox.  The data items to be fetched may be either a single atom
      or an S-expression list.  The currently defined data items that
      can be fetched are:

      ALL             Macro equivalent to:
                      (FLAGS INTERNALDATE RFC822.SIZE ENVELOPE)

      ENVELOPE        The envelope of the message.  The envelope is
                      computed by the server by parsing the RFC 822
                      header into the component parts, defaulting
                      various fields as necessary.

      FAST            Macro equivalent to:
                      (FLAGS INTERNALDATE RFC822.SIZE)















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RFC 1064                         IMAP2                         July 1988


      FLAGS           The flags which are set for this message.
                      This may include the following system flags:

                              \RECENT    Message arrived since
                                          last read of this mail
                                          file
                              \SEEN      Message has been read
                              \ANSWERED  Message has been answered
                              \FLAGGED   Message is "flagged" for
                                          urgent/special attention
                              \DELETED   Message is "deleted" for
                                          removal by later EXPUNGE

      INTERNALDATE    The date and time the message was written to
                      the mailbox.

      RFC822          The message in RFC 822 format.

      RFC822.HEADER   The RFC 822 format header of the message.

      RFC822.SIZE     The number of characters in the message as
                      expressed in RFC 822 format.

      RFC822.TEXT     The text body of the message, omitting the
                      RFC 822 header.

      EXAMPLES:

      A003 FETCH 2:4 ALL
         fetches the flags, internal date, RFC 822 size, and envelope
         for messages 2, 3, and 4.

      A004 FETCH 3 RFC822
         fetches the RFC 822 representation for message 3.

      A005 FETCH 4 (FLAGS RFC822.HEADER)
         fetches the flags and RFC 822 format header for message 4.

   tag STORE sequence data value

      The STORE command alters data associated with a message in the
      mailbox.  The currently defined data items that can be stored are:

      FLAGS           Replace the flags for the message with the
                      argument (in flag list format).

      +FLAGS          Add the flags in the argument to the
                      message's flag list.



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RFC 1064                         IMAP2                         July 1988


      -FLAGS          Remove the flags in the argument from the
                      message's flag list.

         STORE is not allowed if the user does not have write access to
         this mailbox.

         EXAMPLE:  A003 STORE 2:4 +FLAGS (\DELETED)
         marks messages 2, 3, and 4 for deletion.

   tag SEARCH search_criteria

      The SEARCH command searches the mailbox for messages which match
      the given set of criteria.  The unsolicited SEARCH <1#number>
      response from the server is a list of messages which express the
      intersection (AND function) of all the messages.  The currently
      defined criteria are:

      ALL             All messages in the mailbox; the default
                      initial criterion for ANDing.

      ANSWERED        Messages with the \ANSWERED flag set.

      BCC string      Messages which contain the specified string
                      in the envelope's BCC field.

      BEFORE date     Messages whose internal date is earlier than
                      the specified date.

      BODY string     Messages which contain the specified string
                      in the body of the message.

      CC string       Messages which contain the specified string
                      in the envelope's CC field.

      DELETED         Messages with the \DELETED flag set.

      FLAGGED         Messages with the \FLAGGED flag set.

      KEYWORD flag    Messages with the specified flag set.

      NEW             Messages which have the \RECENT flag set but
                      not the \SEEN flag.  This is functionally
                      equivalent to "RECENT UNSEEN".

      OLD             Messages which do not have the \RECENT flag
                      set.





Crispin                                                        [Page 13]