struct talk_to_svr {
       talk_to_svr(const std::string & username)

           : sock_(service), started_(true), username_(username) {}
       void connect(ip::tcp::endpoint ep) {

           sock_.connect(ep);
       }

       void loop() {
           write("login " + username_ + "\n");
           read_answer();
           while ( started_) {

               write_request();
               read_answer();
               boost::this_thread::sleep(millisec(rand() % 7000));

} }

       std::string username() const { return username_; }

... private:

       ip::tcp::socket sock_;
       enum { max_msg = 1024 };
       int already_read_;
       char buff_[max_msg];
       bool started_;
       std::string username_;