Function main

examples/multithread_midiout.cpp:57–121

};

int main()
{
  #if defined(_WIN32) && __has_include(<winrt/base.h>)
  // Necessary for using WinUWP and WinMIDI, must be done as early as possible in your main()
  winrt::init_apartment();
  #endif

  using namespace std::literals;
  using clk = std::chrono::steady_clock;

  const int num_threads = 20;

  // Open our midi output
  libremidi::observer obs;
  auto ports = obs.get_output_ports();
  if (ports.size() == 0)
  {
    std::cerr << "No MIDI outputs are available" << std::endl;
    std::exit(1);
  }
  libremidi::midi_out output;
  output.open_port(ports.front());

  // Create a message queue for communication
  threadsafe_queue<libremidi::message> queue;
  auto midi_writer = [&](std::stop_token stoken) {
    while (!stoken.stop_requested())
    {
      queue.try_enqueue({176, 7, (unsigned char)(rand())});
      std::this_thread::sleep_for(std::chrono::milliseconds(5));
    }
  };

  // Create producer threads
  std::vector<std::jthread> output_threads;
  for (int i = 0; i < 20; i++)
    output_threads.emplace_back(midi_writer);

  // Consume the produced messages
  auto t0 = clk::now();

  int k = 0;
  libremidi::message msg;
  while ((clk::now() - t0) < 5s)
  {
    if (queue.try_dequeue(msg))
    {
      output.send_message(msg);
      k++;
    }
  }
  output_threads.clear();

  // Process remaining messages - most of the time is actually spent inside OS APIs for sending MIDI messages,
  // and those aren't thread-safe so no way out of doing it that way.
  while (queue.try_dequeue(msg))
  {
    k++;