Method start_send

example/cpp11/icmp/ping.cpp:37–62

private:
  void start_send()
  {
    std::string body("\"Hello!\" from Asio ping.");

    // Create an ICMP header for an echo request.
    icmp_header echo_request;
    echo_request.type(icmp_header::echo_request);
    echo_request.code(0);
    echo_request.identifier(get_identifier());
    echo_request.sequence_number(++sequence_number_);
    compute_checksum(echo_request, body.begin(), body.end());

    // Encode the request packet.
    boost::asio::streambuf request_buffer;
    std::ostream os(&request_buffer);
    os << echo_request << body;

    // Send the request.
    time_sent_ = steady_timer::clock_type::now();
    socket_.send_to(request_buffer.data(), destination_);

    // Wait up to five seconds for a reply.
    num_replies_ = 0;
    timer_.expires_at(time_sent_ + chrono::seconds(5));
    timer_.async_wait(std::bind(&pinger::handle_timeout, this));
  }

  void handle_timeout()
  {