anchor.diff:  (defmacro with-tcp-connection-locked (connection &body body)
     `(mezzano.supervisor:with-mutex ((tcp-connection-lock ,connection))
        ,@body))
  -
  -(defun get-tcp-listener-without-lock (local-ip local-port)
  -  (dolist (listener *tcp-listeners*)
  -    (when (and (or (mezzano.network.ip:address-equal
  -                    (tcp-listener-local-ip listener) local-ip)
  -                   (mezzano.network.ip:address-equal
  -                    (tcp-listener-local-ip listener) +ip-wildcard+))
  -               (eql (tcp-listener-local-port listener) local-port))
  -      (return listener))))
  -
  -(defun get-tcp-listener (local-ip local-port)
  -  (mezzano.supervisor:with-mutex (*tcp-listener-lock*)
  -    (get-tcp-listener-without-lock local-ip local-port)))
   
   (defun get-tcp-connection (remote-ip remote-port local-ip local-port)
     (mezzano.supervisor:with-mutex (*tcp-connection-lock*)
  
positive.code: ;; DEFPARAMETER, not DEFCONSTANT, due to cross-compiler constraints.
  (defparameter +ip-wildcard+ (mezzano.network.ip:make-ipv4-address "0.0.0.0"))
  (defconstant +port-wildcard+ 0)
  
  (defvar *tcp-connections* nil)
  (defvar *tcp-connection-lock* (mezzano.supervisor:make-mutex "TCP connection list"))
  
negative.code:   ((connection :initarg :connection :reader tcp-stream-connection)
     (current-packet :initform nil :accessor tcp-stream-packet)))
  
  (defclass tcp-stream (gray:fundamental-character-input-stream
                        gray:fundamental-character-output-stream
                        sys.int::external-format-mixin
                        tcp-octet-stream
                        gray:unread-char-mixin)
    ())
  
  (defmethod mezzano.network:local-endpoint ((object tcp-octet-stream))
    (let ((conn (tcp-stream-connection object)))
      (values (tcp-connection-local-ip conn)
  