rfc1730.txt

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      sessions.  The SELECT command automatically deselects any
      currently selected mailbox before attempting the new selection.
      Consequently, if a mailbox is selected and a SELECT command that
      fails is attempted, no mailbox is selected.

      If the user is permitted to modify the mailbox, the server SHOULD
      prefix the text of the tagged OK response with the "[READ-WRITE]"
      response code.

      If the user is not permitted to modify the mailbox but is
      permitted read access, the mailbox is selected as read-only, and
      the server MUST prefix the text of the tagged OK response to
      SELECT with the "[READ-ONLY]" response code.  Read-only access
      through SELECT differs from the EXAMINE command in that certain
      read-only mailboxes may permit the change of permanent state on a
      per-user (as opposed to global) basis.  Netnews messages marked in
      a user's .newsrc file are an example of such per-user permanent
      state that can be modified with read-only mailboxes.

   Example:    C: A142 SELECT INBOX
               S: * 172 EXISTS
               S: * 1 RECENT
               S: * OK [UNSEEN 12] Message 12 is first unseen
               S: * OK [UIDVALIDITY 3857529045] UIDs valid
               S: * FLAGS (\Answered \Flagged \Deleted \Seen \Draft)
               S: * OK [PERMANENTFLAGS (\Deleted \Seen \*)] Limited
               S: A142 OK [READ-WRITE] SELECT completed


6.3.2.  EXAMINE Command

   Arguments:  mailbox name

   Data:       mandatory untagged responses: FLAGS, EXISTS, RECENT
               optional OK untagged responses: UNSEEN, PERMANENTFLAGS

   Result:     OK - examine completed, now in selected state
               NO - examine failure, now in authenticated state: no
                    such mailbox, can't access mailbox
               BAD - command unknown or arguments invalid

      The EXAMINE command is identical to SELECT and returns the same
      output; however, the selected mailbox is identified as read-only.
      No changes to the permanent state of the mailbox, including
      per-user state, are permitted.






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RFC 1730                         IMAP4                     December 1994


      The text of the tagged OK response to the EXAMINE command MUST
      begin with the "[READ-ONLY]" response code.

   Example:    C: A932 EXAMINE blurdybloop
               S: * 17 EXISTS
               S: * 2 RECENT
               S: * OK [UNSEEN 8] Message 8 is first unseen
               S: * OK [UIDVALIDITY 3857529045] UIDs valid
               S: * FLAGS (\Answered \Flagged \Deleted \Seen \Draft)
               S: * OK [PERMANENTFLAGS ()] No permanent flags permitted
               S: A932 OK [READ-ONLY] EXAMINE completed


6.3.3.  CREATE Command

   Arguments:  mailbox name

   Data:       no specific data for this command

   Result:     OK - create completed
               NO - create failure: can't create mailbox with that name
               BAD - command unknown or arguments invalid

      The CREATE command creates a mailbox with the given name.  An OK
      response is returned only if a new mailbox with that name has been
      created.  It is an error to attempt to create INBOX or a mailbox
      with a name that refers to an extant mailbox.  Any error in
      creation will return a tagged NO response.

      If the mailbox name is suffixed with the server's hierarchy
      separator character (as returned from the server by a LIST
      command), this is a declaration that the client may, in the
      future, create mailbox names under this name in the hierarchy.
      Server implementations that do not require this declaration MUST
      ignore it.

      If a new mailbox is created with the same name as a mailbox which
      was deleted, its unique identifiers MUST be greater than any
      unique identifiers used in the previous incarnation of the mailbox
      UNLESS the new incarnation has a different unique identifier
      validity value.  See the description of the UID command for more
      detail.

   Example:    C: A003 CREATE owatagusiam/
               S: A003 OK CREATE completed
               C: A004 CREATE owatagusiam/blurdybloop
               S: A004 OK CREATE completed




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        Note: the interpretation of this example depends on whether
        "/" was returned as the hierarchy separator from LIST.  If
        "/" is the hierarchy separator, a new level of hierarchy
        named "owatagusiam" with a member called "blurdybloop" is
        created.  Otherwise, two mailboxes at the same hierarchy
        level are created.


6.3.4.  DELETE Command

   Arguments:  mailbox name

   Data:       no specific data for this command

   Result:     OK - delete completed
               NO - delete failure: can't delete mailbox with that name
               BAD - command unknown or arguments invalid

      The DELETE command permanently removes the mailbox with the given
      name.  A tagged OK response is returned only if the mailbox has
      been deleted.  It is an error to attempt to delete INBOX or a
      mailbox name that does not exist.  Any error in deletion will
      return a tagged NO response.

      The value of the highest-used unique indentifier of the deleted
      mailbox MUST be preserved so that a new mailbox created with the
      same name will not reuse the identifiers of the former
      incarnation, UNLESS the new incarnation has a different unique
      identifier validity value.  See the description of the UID command
      for more detail.

   Example:    C: A683 DELETE blurdybloop
               S: A683 OK DELETE completed


6.3.5.  RENAME Command

   Arguments:  existing mailbox name
               new mailbox name

   Data:       no specific data for this command

   Result:     OK - rename completed
               NO - rename failure: can't rename mailbox with that name,
                    can't rename to mailbox with that name
               BAD - command unknown or arguments invalid





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      The RENAME command changes the name of a mailbox.  A tagged OK
      response is returned only if the mailbox has been renamed.  It is
      an error to attempt to rename from a mailbox name that does not
      exist or to a mailbox name that already exists.  Any error in
      renaming will return a tagged NO response.

      Renaming INBOX is permitted; a new, empty INBOX is created in its
      place.

   Example:    C: Z4S9 RENAME blurdybloop owatagusiam
               S: Z4S9 OK RENAME completed


6.3.6.  SUBSCRIBE Command

   Arguments:  mailbox

   Data:       no specific data for this command

   Result:     OK - subscribe completed
               NO - subscribe failure: can't subscribe to that name
               BAD - command unknown or arguments invalid

      The SUBSCRIBE command adds the specified mailbox name to the
      server's set of "active" or "subscribed" mailboxes as returned by
      the LSUB command.  This command returns a tagged OK response only
      if the subscription is successful.

   Example:    C: A002 SUBSCRIBE #news.comp.mail.mime
               S: A002 OK SUBSCRIBE completed


6.3.7.  UNSUBSCRIBE Command

   Arguments:  mailbox name

   Data:       no specific data for this command

   Result:     OK - unsubscribe completed
               NO - unsubscribe failure: can't unsubscribe that name
               BAD - command unknown or arguments invalid

      The UNSUBSCRIBE command removes the specified mailbox name from
      the server's set of "active" or "subscribed" mailboxes as returned
      by the LSUB command.  This command returns a tagged OK response
      only if the unsubscription is successful.





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   Example:    C: A002 UNSUBSCRIBE #news.comp.mail.mime
               S: A002 OK UNSUBSCRIBE completed


6.3.8.  LIST Command

   Arguments:  reference name
               mailbox name with possible wildcards

   Data:       untagged responses: LIST

   Result:     OK - list completed
               NO - list failure: can't list that reference or name
               BAD - command unknown or arguments invalid

      The LIST command returns a subset of names from the complete set
      of all names available to the user.  Zero or more untagged LIST
      replies are returned, containing the name attributes, hierarchy
      delimiter, and name; see the description of the LIST reply for
      more detail.

      An empty ("" string) reference name argument indicates that the
      mailbox name is interpreted as by SELECT. The returned mailbox
      names MUST match the supplied mailbox name pattern.  A non-empty
      reference name argument is the name of a mailbox or a level of
      mailbox hierarchy, and indicates a context in which the mailbox
      name is interpreted in an implementation-defined manner.

      The reference and mailbox name arguments are interpreted, in an
      implementation-dependent fashion, into a canonical form that
      represents an unambiguous left-to-right hierarchy.  The returned
      mailbox names will be in the interpreted form.

      Any part of the reference argument that is included in the
      interpreted form SHOULD prefix the interpreted form.  It should
      also be in the same form as the reference name argument.  This
      rule permits the client to determine if the returned mailbox name
      is in the context of the reference argument, or if something about
      the mailbox argument overrode the reference argument.  Without
      this rule, the client would have to have knowledge of the server's
      naming semantics including what characters are "breakouts" that
      override a naming context.









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           For example, here are some examples of how references
           and mailbox names might be interpreted on a UNIX-based
           server:

               Reference     Mailbox Name  Interpretation
               ------------  ------------  --------------
               ~smith/Mail/  foo.*         ~smith/Mail/foo.*
               archive/      %             archive/%
               #news.        comp.mail.*   #news.comp.mail.*
               ~smith/Mail/  /usr/doc/foo  /usr/doc/foo
               archive/      ~fred/Mail/*  ~fred/Mail/*

           The first three examples demonstrate interpretations in
           the context of the reference argument.  Note that
           "~smith/Mail" should not be transformed into something
           like "/u2/users/smith/Mail", or it would be impossible
           for the client to determine that the interpretation was
           in the context of the reference.

      The character "*" is a wildcard, and matches zero or more
      characters at this position.  The character "%" is similar to "*",
      but it does not match a hierarchy delimiter.  If the "%" wildcard
      is the last character of a mailbox name argument, matching levels
      of hierarchy are also returned.  If these levels of hierarchy are
      not also selectable mailboxes, they are returned with the
      \Noselect mailbox name attribute (see the description of the LIST
      response for more detail).

      Server implementations are permitted to "hide" otherwise
      accessible mailboxes from the wildcard characters, by preventing
      certain characters or names from matching a wildcard in certain
      situations.  For example, a UNIX-based server might restrict the
      interpretation of "*" so that an initial "/" character does not
      match.

      The special name INBOX is included in the output from LIST if it
      matches the input arguments and INBOX is supported by this server
      for this user.  The criteria for omitting INBOX is whether SELECT
      INBOX will return failure; it is not relevant whether the user's
      real INBOX resides on this or some other server.

   Example:    C: A002 LIST "~/Mail/" "%"
               S: * LIST (\Noselect) "/" ~/Mail/foo
               S: * LIST () "/" ~/Mail/meetings
               S: A002 OK LIST completed






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RFC 1730                         IMAP4                     December 1994


6.3.9.  LSUB Command

   Arguments:  reference name
               mailbox name with possible wildcards

   Data:       untagged responses: LSUB

   Result:     OK - lsub completed
               NO - lsub failure: can't list that reference or name
               BAD - command unknown or arguments invalid

      The LSUB command returns a subset of names from the set of names
      that the user has declared as being "active" or "subscribed".
      Zero or more untagged LSUB replies are returned.  The arguments to
      LSUB are in the same form as those for LIST.

   Example:    C: A002 LSUB "#news." "comp.mail.*"
               S: * LSUB () "." #news.comp.mail.mime