31 const static auto startup_time = std::chrono::high_resolution_clock::now();
39 return std::chrono::duration_cast<std::chrono::milliseconds>(std::chrono::high_resolution_clock::now() - startup_time).count();
42 return std::chrono::duration_cast<std::chrono::microseconds>(std::chrono::high_resolution_clock::now() - startup_time).count();
47 std::this_thread::sleep_for(std::chrono::milliseconds(ms));
52 std::this_thread::sleep_for(std::chrono::microseconds(us));