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Thread: Thread safe or not

  1. #1
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    Default Thread safe or not

    Look at following code n pls let me know whether my Worker class is thread safe or not. I have a Worker class cpp as follows: m_str is Qstring member variable in Worker class n m_thread is QThread in same class.

    Qt Code:
    1. Worker::Worker() {
    2. m_thread = new QThread;
    3. moveToThread(m_thread);
    4.  
    5. connect(m_thread, SIGNAL(started()), this, SLOT(process()));
    6. connect(m_thread, SIGNAL(finished()), this, SLOT(quit()));
    7.  
    8. connect(m_thread, SIGNAL(finished()), m_thread, SLOT(deleteLater()));
    9. }
    10.  
    11. Worker::~Worker() {
    12.  
    13. }
    14.  
    15. void Worker::doStart()
    16. {
    17. .... // not touching m_str
    18. m_thread->start(); // this always last stmt. in this function
    19. }
    20.  
    21. void Worker::process() {
    22. m_str = QString("Hello!");
    23.  
    24. m_thread->quit();
    25. }
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    and in main.cpp file

    Qt Code:
    1. int main(int argc, char *argv[])
    2. {
    3. QApplication app(argc, argv);
    4.  
    5. Worker* worker = new Worker();
    6.  
    7. worker->doStart();
    8.  
    9. worker->thread()->wait();
    10.  
    11. worker->deleteLater();
    12.  
    13. return app.exec();
    14. }
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  2. #2
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    Default Re: Thread safe or not

    No, it's not thread safe. No QObject based class is thread-safe and you are accessing QThread which is derived from QObject (and possibly your Worker class is also QObject derived). However your class is reentrant.
    Your biological and technological distinctiveness will be added to our own. Resistance is futile.

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