semaphores.cpp Example File
threads/semaphores/semaphores.cpp
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** Copyright (C) 2005-2005 Trolltech AS. All rights reserved.
**
** This file is part of the documentation of the Qt Toolkit.
**
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** accordance with the Qt Preview License Agreement provided with the
** Software.
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** information about Qt Commercial License Agreements.
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** WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
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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();
};
void Producer::run()
{
for (int i = 0; i < DataSize; ++i) {
freeBytes.acquire();
buffer[i % BufferSize] = "ACGT"[(int)rand() % 4];
usedBytes.release();
}
}
class Consumer : public QThread
{
public:
void run();
};
void Consumer::run()
{
for (int i = 0; i < DataSize; ++i) {
usedBytes.acquire();
fprintf(stderr, "%c", buffer[i % BufferSize]);
freeBytes.release();
}
fprintf(stderr, "\n");
}
int main(int argc, char *argv[])
{
QCoreApplication app(argc, argv);
Producer producer;
Consumer consumer;
producer.start();
consumer.start();
producer.wait();
consumer.wait();
return 0;
}