bool QSemaphore::tryAquire(timeout) -- never times out on an active semaphore

class myThead : public QThread {
    int _timeout, _consume;
    QSemaphore *_startingGate , *_semaphore;
public:
    myThead(int timeout, int consume,
            QSemaphore* gate,QSemaphore* sem) :
            _timeout(timeout), _consume(consume),
            _startingGate(gate), _semaphore(sem)
    { }
protected:
    virtual void run() {
        _startingGate->acquire(1); // wait for everbody else
        forever {
            if(!_semaphore->tryAcquire(_consume, _timeout)) { break; }
            _semaphore->release(_consume);
        }
        qDebug() << "timed(" << _timeout << ") out trying to consume:" << _consume;
    }
};

int main(int argc, char *argv[]) {
    QSemaphore gate(2), sem(1);
    myThead big(2000, 2, &gate, &sem); // big consumer will never win
    myThead small(1000, 1, &gate, &sem);
    big.start(); small.start();
    gate.tryAcquire(INT_MAX, 1000); // wait for all threads to start
    gate.release(2); // release everyone
    qDebug() << "everyone is running, now sleeping";
    gate.tryAcquire(INT_MAX, 10000);
    qDebug() << "did big consumer timeout yet:" << (big.isRunning()?"no":"yes");
    qDebug() << "timing out everyone";
    sem.acquire(1);
    big.wait(); small.wait();
    qDebug() << "everyone is dead";
    return 0;
}