anchor.diff:      (write-uint16 port fs)
       (write-byte +node-type-hidden+ fs)
       (write-byte +protocol-tcpip4+ fs)
  +    (write-uint16 +highest-version-supported+ fs)
       (write-uint16 +lowest-version-supported+ fs)
  -    (write-uint16 +highest-version-supported+ fs)
       (write-uint16 node-name-length fs)
       (write-string node-name fs)
       (write-uint16 extra-field-length fs)
  
positive.code: ;; 2 bytes: Port
  ;; 1 byte:  Node type      [77 means Erlang node, 72 means hidden node]
  ;; 1 byte:  Protocol       [0 means TCP/IP v4]
  ;; 2 bytes: Lowest version supported
  ;; 2 bytes: Highest version supported
  ;; 2 bytes: Node name length
  ;; N bytes: Node name
  ;; 2 bytes: Extra field length
  
negative.code: ;; 2 bytes: Listening port
  ;; 1 byte:  72                [hidden node (not Erlang node)]
  ;; 1 byte:  0                 [protocol: tcp/ip v4]
  ;; 2 bytes: 5                 [highest version supported]
  ;; 2 bytes: 5                 [lowest version supported]
  ;; 2 bytes: Length of node name
  ;; N bytes: Node name
  ;; 2 bytes: Length of the Extra field
  