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50
51#include <QtCore>
52
53#include <stdio.h>
54#include <stdlib.h>
55
56//! [0]
57const int DataSize = 100000;
58
59const int BufferSize = 8192;
60char buffer[BufferSize];
61
62QSemaphore freeBytes(BufferSize);
63QSemaphore usedBytes;
64//! [0]
65
66//! [1]
67class Producer : public QThread
68//! [1] //! [2]
69{
70public:
71 void run() override
72 {
73 for (int i = 0; i < DataSize; ++i) {
74 freeBytes.acquire();
75 buffer[i % BufferSize] = "ACGT"[QRandomGenerator::global()->bounded(highest: 4)];
76 usedBytes.release();
77 }
78 }
79};
80//! [2]
81
82//! [3]
83class Consumer : public QThread
84//! [3] //! [4]
85{
86 Q_OBJECT
87public:
88 void run() override
89 {
90 for (int i = 0; i < DataSize; ++i) {
91 usedBytes.acquire();
92 fprintf(stderr, format: "%c", buffer[i % BufferSize]);
93 freeBytes.release();
94 }
95 fprintf(stderr, format: "\n");
96 }
97};
98//! [4]
99
100//! [5]
101int main(int argc, char *argv[])
102//! [5] //! [6]
103{
104 QCoreApplication app(argc, argv);
105 Producer producer;
106 Consumer consumer;
107 producer.start();
108 consumer.start();
109 producer.wait();
110 consumer.wait();
111 return 0;
112}
113//! [6]
114
115#include "semaphores.moc"
116

source code of qtbase/examples/corelib/threads/semaphores/semaphores.cpp