semaphores.cpp Example File

threads/semaphores/semaphores.cpp
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#include <QtCore> #include <stdio.h> #include <stdlib.h> const int DataSize = 100000; const int BufferSize = 8192; char buffer[BufferSize]; QSemaphore freeBytes(BufferSize); QSemaphore usedBytes; class Producer : public QThread { public: void run() override { qsrand(QTime(0,0,0).secsTo(QTime::currentTime())); for (int i = 0; i < DataSize; ++i) { freeBytes.acquire(); buffer[i % BufferSize] = "ACGT"[(int)qrand() % 4]; usedBytes.release(); } } }; class Consumer : public QThread { Q_OBJECT public: void run() override { for (int i = 0; i < DataSize; ++i) { usedBytes.acquire(); fprintf(stderr, "%c", buffer[i % BufferSize]); freeBytes.release(); } fprintf(stderr, "\n"); } signals: void stringConsumed(const QString &text); protected: bool finish; }; int main(int argc, char *argv[]) { QCoreApplication app(argc, argv); Producer producer; Consumer consumer; producer.start(); consumer.start(); producer.wait(); consumer.wait(); return 0; } #include "semaphores.moc"