Function echo

example/echo_server.cpp:22–37

tag::echo[]

// tag::echo[]
cobalt::promise<void> echo(cobalt::io::stream_socket socket)
{
  try // <1>
  {
    char data[4096];
    while (socket.is_open()) // <2>
    {
      std::size_t n = co_await socket.read_some(boost::asio::buffer(data)); // <3>
      co_await cobalt::io::write(socket, boost::asio::buffer(data, n)); // <4>
    }
  }
  catch (std::exception& e)
  {
    std::printf("echo: exception: %s\n", e.what());
  }
}
// end::echo[]