[Boost-users] boost::Asio async_accept not throwing exception

Hi, I have modified the sample program provided in the asio samples, just to accept a connection like this void TCPServer::StartAccept() { try { TCPConnection::Pointer NewConnection=TCPConnection::Create(Acceptor.io_service()); Acceptor.async_accept(NewConnection->socket(),boost::bind(&TCPServer::HandleAccept,this, NewConnection,boost::asio::placeholders::error)); } catch(std::exception& e) { cout<<"exception"<<endl; } } Another program is already listening on the port "13" (A service version of the same program). When this new program tries to listen (async_accept) on port "13", no exception is thrown!. How can I check weather the port is already open? Thanks, Lloyd