boost::asio and socket ownership

问题

I've two classes (Negotiator, Client), both has their own boost::asio::ip::tcp::socket. Is there a way to transfer socket object to Client after negotiation is finished. I'm looking forward to do something like that:

 boost::asio::ip::tcp::socket sock1(io);
 //...
 boost::asio::ip::tcp::socket sock2;
 sock2.assign(sock1); 

This operation must guarantee that the connection won't be closed when sock1 is destroyed.

回答1:

I think that you could:

• obtain sock1's native handle with the native() member function
• dup() (or WSADuplicateSocket()) sock1's native handle
• pass the dup()-ed handle to sock2 with the assing() member function

However:

• I'm not sure as I never tried that
• If you want to transfer (instead of sharing) the socket from Negotiator to Client, Dan's suggestion of using dynamic allocation is probably simpler, using unique_ptr (or auto_ptr)

回答2:

Create the socket on the heap (new), and pass the pointer from the negotiator to the client.

回答3:

As of the current version of Boost, you would now get the handle with

boost::asio::ip::tcp::socket::my_socket;
auto my_handle = my_socket.native_handle();

instead of the old native() member function.

来源：https://stackoverflow.com/questions/2966323/boostasio-and-socket-ownership