6. The UPDATE State

When the client issues the QUIT command from the TRANSACTION state, the POP3 session enters the UPDATE state. (Note that if the client issues the QUIT command from the AUTHORIZATION state, the POP3 session terminates but does NOT enter the UPDATE state.)

If a session terminates for some reason other than a client-issued QUIT command, the POP3 session does NOT enter the UPDATE state and MUST not remove any messages from the maildrop.

      QUIT

         Arguments: none

         Restrictions: none

         Discussion:
             The POP3 server removes all messages marked as deleted from
             the maildrop.  It then releases any exclusive-access lock
             on the maildrop and replies as to the status of these
             operations.  The TCP connection is then closed.

         Possible Responses:
             +OK

         Examples:
             C: QUIT
             S: +OK dewey POP3 server signing off (maildrop empty)
                ...
             C: QUIT
             S: +OK dewey POP3 server signing off (2 messages left)
                ...