class TCPClient {
 public:
  TCPClient(boost::asio::io_service& io_service)
    : socket_(io_service) {
    // Connect
    [...]
    // Asynchronous read
    socket_.async_read_some(boost::asio::buffer(buffer, buffer.size()),
                            boost::bind(&TCPClient::handlerRead,
                                        this,
                                        placeholders::error,
                                        placeholders::bytes_transferred));
  ~TCPClient() {}
  void handlerRead(const boost::system::error_code& ec, uint32_t bytes) {
    if (!ec) {
      // process
      [...]
      socket_.async_read_some(
        boost::asio::buffer(buffer, buffer.size()),
        boost::bind(&TCPClient::handlerRead,
                    this,
                    placeholders::error,
                    placeholders::bytes_transferred));
  int getSocketFd() {
    return socket_.native_handle();
 private:
  boost::asio::tcp::socket socket_;