#include <atomic>
#include <thread>
#include <chrono>
#include <iostream>
#include <pthread.h>
 
class cancellation_token {
public:
    cancellation_token() : status(false) {}
 
    bool is_cancelled() const { return status.load(std::memory_order_acquire); }
 
    void cancel() { status.store(true, std::memory_order_release); }
 
private:
    std::atomic<bool> status;
};
 
int main() {
    cancellation_token token;
    std::thread t([&token]{
        std::cout << "I'm in your thread\n";
        while(!token.is_cancelled()) {
            std::cout << "foo\n";
        }
    });
    pthread_yield();
    for(int i = 0; i < 100; ++i) std::cout << "bar\n";
    token.cancel();
    std::cout << "done\n";
    t.join();
}
 

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