why threads id are same?

iskenderoguz

I create a class to use multi threads

class ClThread : public QThread
{
public:
    ClThread();
    void run();
signals:
public slots:
};

I wrote thread id in constructor
ClThread::ClThread()
{
    qDebug()<<"thread : "<<thread()->currentThreadId();
}

I call it from main class

ClThread *clthread1 = new ClThread();
ClThread *clthread2 = new ClThread();

Also I tried QRunnable

class ClThread : public QRunnable
{
public:
    ClThread();
    void run();
signals:
public slots:
};

ClThread::ClThread()
{
    qDebug()<<"thread : "<<QThread::currentThreadId();
}

ClThread *clthread1 = new ClThread();
ClThread *clthread2 = new ClThread();

QThreadPool::globalInstance()->start(clthread1);
QThreadPool::globalInstance()->start(clthread2);

But clthread1 and clthread2 threads id are same always. this is normal ? these are different threads ?

JKSH

@iskenderoguz said:

I call it from main class

ClThread *clthread1 = new ClThread();
ClThread *clthread2 = new ClThread();
...
But clthread1 and clthread2 threads id are same always. this is normal ?

Yes, this is normal.

Your code runs the constructors in the main thread. It does not start any new threads. Think of it this way:

QFile* file = new QFile("myfile.txt"); // This does NOT create a new file on your hard drive
QThread* thread = new QThread(); // This does NOT create a new thread in your program

// ===

file->open(QFile::WriteOnly); // This creates a new file on your hard drive
thread->start(); // This creates a new thread in your program

If you want to start your new thread, you must call QThread::start(). Then, the code inside QThread::run() will start running in a new thread.