anchor.diff:      {ok,{_,P2,OptsVals3, <<"abcde">>}} = gen_udp:recv(S1, 0, Timeout),
       ?P("S1 recv: "
          "~n   OptsVals3: ~p", [OptsVals3]),
  +    ?SLEEP(100),
  +
       verify_sets_eq(OptsVals3, OptsVals2),
       TestSend andalso
           begin
  
positive.code:     %%
      ?P("send/3: S2 -> S1"),
      ok = gen_udp:send(S2, {Addr,P1}, <<"abcde">>),
      ?P("send/4: S1 -> S2"),
      ok = gen_udp:send(S1, Addr, P2, <<"fghij">>),
      TestSend andalso
  
negative.code:                "~n   ~p", [OptsVals]),
              case gen_udp:send(S2, {Addr,P1}, OptsVals, <<"12345">>) of
                  ok ->
                      ?SLEEP(100),
                      ok;
                  {error, enoprotoopt = Reason2} ->
                      ?SKIPT(?F("send (2) failed: ~p", [Reason2]))
  