anchor.diff:    (multiple-value-setq (send-data send-seq)
       (funcall encode-function message))
     (setq send-data-length (length send-data))
  -
  +  (setq recv-data (make-array max-receive-length
  +                              :element-type '(unsigned-byte 8)
  +                              :initial-element 0))
     ;; Define basic network operations
     (labels ((send ()
                (let ((nbytes (usocket:socket-send socket send-data send-data-length)))
  
positive.code:                     &aux
                      send-seq send-data send-data-length
                      (send-retries *socket-sync-retries*)
                      recv-message recv-seq
                      (sockets (list socket)))
    "sync messages on single socket"
    (declare (type usocket:datagram-usocket socket))
  
negative.code:                (declare (ignore return-sockets))
                 real-time))
             (recv ()
               (multiple-value-bind (return-recv-data recv-data-length)
                   (usocket:socket-receive socket recv-data max-receive-length)
                 (when (plusp recv-data-length)
                   (multiple-value-setq (recv-message recv-seq)
                     (funcall decode-function recv-data))
                   (= send-seq recv-seq)))))
  