anchor.diff:  p_read_reply(Port) ->
       receive
           {Port, {data, <<Size:32/integer-signed-little,Msg/binary>>}} ->
  -            {Size, Msg}
  +            {ok, {Size, Msg}}
  +    after
  +        ?WORKER_REPLY_TIMEOUT ->
  +            {error, worker_timeout}
       end.
  
positive.code: -define(kGetTokenId,3).
  -define(kSubmitPayload,4).
  -define(kError,5).
  
  
  %%%===================================================================
  
negative.code:     %% Send a kEcho request to the worker
      lager:info("Sending kEcho request to worker process."),
      p_write_request(WorkerPort, ?kEcho, <<"Ping">>),
      {ok, {Size, Msg}} = p_read_reply(WorkerPort),
      lager:info("Received kEcho reply from worker: size: ~p, msg: ~p", [Size, Msg]),
      {ok, #{worker => WorkerPort}}.
  
  