int seconds = 10;

const auto usage = [] {

std::cerr << "usage: optional lifetime is one integer in seconds (1..3600)\n";

return 2;

};

if (argc > 2) return usage();

if (argc == 2) {

const std::string_view argument(argv[1]);

const auto parsed = std::from_chars(argument.data(), argument.data() + argument.size(), seconds);

if (parsed.ec != std::errc() || parsed.ptr != argument.data() + argument.size()

|| seconds <= 0 || seconds > 3600) return usage();

}

auto listened = server.listen();

if (!listened.ok()) {

std::cerr << listened.message() << '\n';

return 1;

}

std::cout << "PORT=" << server.get_bound_port(0) << std::endl;

const auto deadline = std::chrono::steady_clock::now() + std::chrono::seconds(seconds);

while (server.is_running() && std::chrono::steady_clock::now() < deadline) {

std::this_thread::sleep_for(std::chrono::milliseconds(10));

}

// Only the controlling thread joins workers.

server.stop();

return 0;