Application doesn't reaaly close

[zodd]

Hello,

I noticed that if I close my application during a long task like "reading a big file, the GUI window close well but application only stop at the end of the reading. So I did some test, and if I do this:

void MYGUI::on_pushButton_ReadFile_clicked()
{
    int i=0;
    while(1)
    {
 
        i++;
         qDebug() << "TEST" << i;
         QCoreApplication::processEvents();
    }
}

void MYGUI::on_pushButton_ReadFile_clicked()
{
    int i=0;
    while(1)
    {

        i++;
         qDebug() << "TEST" << i;
         QCoreApplication::processEvents();
    }
}

To copy to clipboard, switch view to plain text mode 

when I close the application by clicking on the cross on the upper right of my application window (on Windows 10), it close well the window, but the application still run in the task manager and I have to manually kill it in the task manager or in the cmd prompt with taskkill /IM myApp.exe /F.

Is someone has a clue to be sure to close the entire application when needed even if processing a "big task" please?