anchor.diff:           ;; Waiting for ACK
            (when (and (eql seq (tcp-connection-r-next connection))
                       (logtest flags +tcp4-flag-ack+))
  +           ;; Remote have sended ACK , connection closed
              (detach-tcp-connection connection)
              (setf (tcp-connection-state connection) :closed)))
           (t
  
positive.code:                 (setf (tcp-connection-state connection) :connection-aborted)
                  (detach-tcp-connection connection))))
          (:syn-received
           (cond ((and (eql flags +tcp4-flag-ack+)
                       (eql seq (tcp-connection-r-next connection))
                       (eql ack (tcp-connection-s-next connection)))
                  (setf (tcp-connection-state connection) :established))
                 ((and (logtest flags +tcp4-flag-syn+)
                       (eql ack (1- (tcp-connection-s-next connection))))
                  (format t "TCP: Ignore duplicated syn packets."))
                 (t
                  ;; Aborting connection
  
negative.code:                           ;; Simultaneous close
                            (setf (tcp-connection-state connection) :closing)))
                       ((logtest flags +tcp4-flag-ack+)
                        ;; Remote saw our FIN
                        (setf (tcp-connection-state connection) :fin-wait-2))))
               (tcp4-receive-data connection data-length end header-length packet seq start :fin-wait-1)))
          (:fin-wait-2
  