anchor.diff:  %%  2. the list of alternative name servers
   %%
   res_gethostbyaddr(Addr, IP, Timer) ->
  -    case res_query(Addr, in, ptr, [], Timer) of
  +    case res_query(Addr, in, ?S_PTR, [], Timer) of
   	{ok, Rec} ->
   	    inet_db:res_gethostbyaddr(IP, Rec);
   	{error,{qfmterror,_}} -> {error,einval};
  
positive.code: 	    end
      end.
  
  query_udp(_S, _Id, _Buffer, _IP, _Port, 0, _Verbose) ->
      timeout;
  query_udp(S, Id, Buffer, IP, Port, Timeout, Verbose) ->
      ?verbose(Verbose, "Try UDP server : ~p:~p (timeout=~w)\n",
  	     [IP,Port,Timeout]),
      case
  
negative.code: 		    case gen_tcp:recv(S, 0, Timeout) of
  			{ok, Answer} ->
  			    gen_tcp:close(S),
  			    case decode_answer(Answer, Msg, Verbose) of
  				{ok, _} = OK -> OK;
  				{error, badid} -> {error, servfail};
  				Error -> Error
  