#include <iostream>
#include <thread>
#include <condition_variable>
#include <mutex>

// https://en.cppreference.com/w/cpp/thread/thread
// https://en.cppreference.com/w/cpp/thread/mutex
// https://en.cppreference.com/w/cpp/thread/condition_variable

std::mutex mtx;
std::condition_variable cv;
bool ready = false;

void worker() {
    std::unique_lock<std::mutex> lock(mtx);
    cv.wait(lock, [] { return ready; }); // Wait until 'ready' is set to true
    std::cout << "Daemon process woke up!" << std::endl;
}

int main() {
    std::thread daemon(worker);

    std::this_thread::sleep_for(std::chrono::seconds(5));
    {
        std::lock_guard<std::mutex> lock(mtx);
        ready = true;
    }
    cv.notify_one();

    daemon.join();
    return 0;
}