C++ examples - ppqueue.cpp : Can't send reply to client

[pvthuyet]

• Reproduce: (window environment)

1. run ppqueue.exe
2. run ppworker.exe
3. run lpclient.exe

• Result: client can't received result

• Root cause
  in ppqueue.cpp line 126

        //  Handle worker activity on backend
        if (items [0].revents & ZMQ_POLLIN) {
            zmsg msg (backend);
            std::string identity(msg.unwrap ());

msg.unwrap() will remove client's address. Therefore, message can't deliver to client
I dumped data before and after call msg.unwrap()

 ******* Before call unwrap()
--------------------------------------
[004] 0001
[005] 008000002a
[000]
[001] 1

 ******* After call unwrap()
--------------------------------------
[000]
[001] 1