anchor.diff:    when is_port(Client) ->
       ok = send(Client, Raw),
       {noreply, State};
  -
   handle_cast({reply, Channel, Method, Protocol}, State = #s{client = Client})
     when is_port(Client) ->
       ok = send(Client, Channel, Method, Protocol),
       {noreply, State};
  -
   handle_cast({forward, Raw, Channel, Method, Protocol},
               State = #s{server = Server, policies = Policies})
     when is_port(Server) ->
       ok = intercept(Server, Raw, Channel, Method, Protocol, Policies),
       {noreply, State}.
  -
  -
   
   -spec handle_info(_, #s{}) -> {noreply, #s{}} | {stop, normal, #s{}}.
   %% @hidden
  
positive.code:     end.
  
  -spec send(inet:socket(), non_neg_integer(), method(), protocol()) -> ok.
  %% @doc
  send(Sock, 0, Method, Protocol) ->
      rabbit_writer:internal_send_command(Sock, 0, Method, Protocol);
  send(Sock, Channel, Method, Protocol) ->
  
negative.code:             Error
      end.
  
  %% @doc
  reply(Conn, Raw) ->
      gen_server:cast(Conn, {reply, Raw}).
  
  %% @doc
  reply(Conn, Channel, Method, Protocol) ->
      gen_server:cast(Conn, {reply, Channel, Method, Protocol}).
  
  %% @doc
  replay(Conn, StartOk, Replay, Protocol) ->
      gen_server:call(Conn, {replay, StartOk, Replay, Protocol}).
  
  %% @doc
  forward(Conn, Raw, Channel, Method, Protocol) ->
      gen_server:cast(Conn, {forward, Raw, Channel, Method, Protocol}).
  
  