anchor.diff:      Recv = fun(Sock) ->
                      socket:recvfrom(Sock)
              end,
  -    ok = api_b_send_and_recv_udp(inet, Send, Recv),
  +    InitState = #{domain => inet,
  +                  send   => Send,
  +                  recv   => Recv},
  +    ok = api_b_send_and_recv_udp(InitState),
       tc_end().
   
   
  
positive.code:                            ERROR
                     end
             end,
      ok = api_b_send_and_recv_udp(inet, Send, Recv),
      tc_end().
  
  
  %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  
  api_b_send_and_recv_udp(Domain, Send, Recv) ->
      SockSrc = sock_open(Domain, dgram, udp),
      LAddr   = which_local_addr(Domain),
      LSA     = #{family => Domain, addr => LAddr}, 
      sock_bind(SockSrc, LSA),
      SockDst = sock_open(Domain, dgram, udp),
      sock_bind(SockDst, LSA),
      Dst     = sock_sockname(SockDst),
      ok      = Send(SockSrc, ?BASIC_REQ, Dst),
      {ok, {Src, ?BASIC_REQ}} = Recv(SockDst),
      ok      = Send(SockDst, ?BASIC_REP, Src),
      {ok, {Dst, ?BASIC_REP}} = Recv(SockSrc),
      socket:close(SockSrc),
      socket:close(SockDst),
      ok.
  
  
  
  
negative.code:     ok = await_evaluator_finish([Evaluator]).
  
  
  
  %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  
  %% Basically send and receive on an IPv4 UDP (dgram) socket using
  