anchor.diff:      ?P("[csock 1] await reply message 1"),
       receive
           {udp, CSock1, _, _, <<"hopp">>} ->
  -            ?P("[csock 1] received expected reply message 1")
  +            ?P("[csock 1] received expected reply message 1"),
  +            ok;
  +
  +        {'EXIT', Server, SReason1} ->
  +            ?P("received unexpected server exit (1):"
  +               "~n.     ~p", [SReason1]),
  +            ct:fail({unexpected_server_exit, 1, SReason1})
  +
       after 5000 ->
               ?P("receive (1) timeout:"
                  "~n      ~p", [mq()]),
  
positive.code: 
      ?P("[csock 1] await reply message 3"),
      receive
          {udp, CSock, _, _, <<"hopp">>} ->
              ?P("received expected reply message 3")
      end,
  
  
  
negative.code:     end,
      
      ?P("cleanup"),
      (catch gen_udp:close(CSock1)),
      (catch gen_udp:close(CSock2)),
  
      ?P("done"),
      ok.
  