#### Source listing for Daytime.5

    //
    // server.cpp
    // ~~~~~~~~~~
    //
    // Copyright (c) 2003-2025 Christopher M. Kohlhoff (chris at kohlhoff dot com)
    //
    // Distributed under the Boost Software License, Version 1.0. (See accompanying
    // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
    //

    #include <array>
    #include <ctime>
    #include <iostream>
    #include <string>
    #include <asio.hpp>

    using asio::ip::udp;

    std::string make_daytime_string()
    {
      using namespace std; // For time_t, time and ctime;
      time_t now = time(0);
      return ctime(&now);
    }

    int main()
    {
      try
      {
        asio::io_context io_context;

        udp::socket socket(io_context, udp::endpoint(udp::v4(), 13));

        for (;;)
        {
          std::array<char, 1> recv_buf;
          udp::endpoint remote_endpoint;
          socket.receive_from(asio::buffer(recv_buf), remote_endpoint);

          std::string message = make_daytime_string();

          std::error_code ignored_error;
          socket.send_to(asio::buffer(message),
              remote_endpoint, 0, ignored_error);
        }
      }
      catch (std::exception& e)
      {
        std::cerr << e.what() << std::endl;
      }

      return 0;
    }

Return to Daytime.5 - A synchronous UDP daytime server