rfc1203.txt

著名的RFC文档,其中有一些文档是已经翻译成中文的的.

      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 a solicited 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
      check that the user is permitted read access to this mailbox.
      Prior to returning an OK to the client, the server must send an
      solicited 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.
      It is further recommended that servers should send an unsolicited
      READONLY message if the mailbox that has been selected is not



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      writable by the user.

      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 path of the
      mailbox on the current servers), though it could reflect any
      server-specific naming convention for the namespace of mailboxes.
      Such a namespace need not and should not be viewed as being
      equivalent or linked to the server machine's file system.

      EXAMPLES: A002 SELECT INBOX  ;; selects the default mailbox.
                A002 197 EXISTS    ;; server says 197 messages in INBOX
                A002 5 RECENT      ;; server says 5 are recent.
                A002 OK Select complete.
      or
                A003 SELECT /usr/fred/my-mail.txt
                 ;; select a different user specified 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 must send a
      solicited <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,
      a solicited <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 mailbox are expunged you will
      receive 5 "5 EXPUNGE" responses for message 5.  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 mailbox
      the server must guarantee both the integrity of the mailbox and



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      the views of it held by the clients.

      EXPUNGE is not allowed if the user does not have write access to
      this mailbox.  If a user does not have write access to the mailbox
      then the server is required to signal this fact by replying with a
      NO response with a suitable text string that can be presented to
      the user explaining that the mailbox is read-only.  It is further
      recommended that servers send an unsolicited READONLY message to
      clients that attempt an expunge operation on a read only 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 must return a solicited <n> COPY response for
      each message copied.

      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.  If a user does not have write access to the
      destination mailbox then the server is required to signal this
      fact by replying with a NO response with a suitable text string
      that can be presented to the user explaining that the mailbox is
      read-only.  It is further recommended that servers send an
      unsolicited READONLY message to clients that attempt to copy to a
      read only mailbox.  IMAP3 does not specify "where" the message
      will be put in the mailbox to which it has been copied.

   tag FETCH sequence fetch_att

      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 attributes that can be fetched are
      any of those mentioned specifically below along with any generic,
      canonical or concrete key.  The set of predefined generic keys is:
      {BCC, BODY, CC, FROM, HEADER, SIZE, SUBJECT, TEXT, TO}.  The set
      of predefined canonical keys is {$CC, $FROM, $SUBJECT, $TO}.  The
      value returned by the server for a non-existent or non-meaningful
      key is defined to be the null value, NIL.

      ALL             Equivalent to:
                      (FLAGS INTERNALDATE RFC822.SIZE ENVELOPE)

      ENVELOPE        The envelope of the message.  The envelope is
                      computed by the server by parsing the header,



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                      i.e., the RFC 822 header for an RFC822 format
                      message, into the component parts, defaulting
                      various fields as necessary.

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

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

                              \RECENT    Message arrived since
                                          last read of this mailbox
                              \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.

      A006 FETCH 42 $SUBJECT
      A006 FETCH $SUBJECT "Some subject text..."
      A006 OK FETCH completed ok.
         fetches the canonical subject field.



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      A007 FETCH 42 APPARENTLY-TO
      A007 FETCH APPARENTLY-TO NIL
      A007 OK FETCH found no value.
         fetches the concrete apparently-to field.

   tag STORE sequence data value

      The STORE command alters the values associated with particular
      keys for a message in the mailbox.  As is the case for the FETCH
      command, any generic, canonical or concrete key may be used to
      index the value provided.  In addition to these, the following
      pre-defined keys are provided.

   FLAGS           Replace the flags for the message with the
                   argument (in flag list format).
                  The server must respond with a solicited STORE FLAGS
                  message, showing the new state of the flags after
                  the store.

   +FLAGS          Add the flags in the argument to the
                   message's flag list.
                 The server must respond with a solicited STORE FLAGS
                 message, showing the new state of the flags after
                 the store.

  -FLAGS          Remove the flags in the argument from the
                  message's flag list.
                 The server must respond with a solicited STORE FLAGS
                 message, showing the new state of the flags after
                 the store.

  RFC822.HEADER   Replace the header of the message(s) with that
                  specified.  This allows users to use their mailboxes
                  as databases with header fields as keys.
                  The server must respond with solicited
                  STORE RFC822.HEADER, STORE RFC822.SIZE and
                  STORE ENVELOPE messages,  showing the new state
                  of the reparsed header after the store.

  RFC822.TEXT     Replace the body of the messages with that specified.
                  The server must respond with solicited
                  STORE RFC822.TEXT and STORE RFC822.SIZE messages,
                  showing the new state of the message after the store.

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

         The server is required to send a solicited STORE response for



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         each store operation that results in a format transformation by
         the server.  For example, the server is required to send a
         STORE FLAGS response when the client performs a STORE +FLAGS or
         a STORE -FLAGS, since the client may not easily be able to know
         what the result of this command will be.  Similarly, if the
         client emits a STORE FROM command then the server should
         respond with a suitable STORE FROM response because the client
         would be sending a string value to be stored and the server
         should transform this into a set of addresses.  In general,
         however, although it is legal for the server to send a
         solicited STORE response for each STORE operation, this is
         discouraged, since it might result in the retransmission of
         very large and unnecessary amounts of data that have been
         stored.

         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 server response SEARCH (criteria)
      (numbers) gives the set of messages which match the conjunction of
      the criteria specified.  In addition to each of the search
      criteria there is its logical inverse.  The logical inverse
      criterion is denoted by the ~ (tilda) sign.