[Qt-interest] QFile* threads

[_h_]

Hi,
In one of my qt application I am using multiple instance of
QFileDialog by taking object pointer.
When observing process stack of this application, it shows following...

Thread 3 (Thread 183630768 (LWP 10648)):
#0 0x008e348d in pthread_cond_wait@@GLIBC_2.3.2 ()
#1 0x02a34178 in QWaitCondition::wait ()
#2 0x06bbbced in QFileSystemModel::sort ()
#3 0x02a335a0 in QThread::setPriority ()
#4 0x008e0d78 in start_thread () from /lib/tls/libpthread.so.0
#5 0x05e613fa in clone () from /lib/tls/libc.so.6
Thread 2 (Thread 173140912 (LWP 10649)):
#0 0x05e5a757 in ___newselect_nocancel () from /lib/tls/libc.so.6
#1 0x02b55bbf in QEventDispatcherUNIX::select ()
#2 0x02b56c50 in QEventDispatcherUNIXPrivate::doSelect ()
#3 0x02b57117 in QEventDispatcherUNIX::processEvents ()
#4 0x02b26b6d in QEventLoop::processEvents ()
#5 0x02b26eed in QEventLoop::exec ()
#6 0x02a30087 in QThread::exec ()
#7 0x02b0b91e in QFSFileEngine::rmdir ()
#8 0x02a335a0 in QThread::setPriority ()
#9 0x008e0d78 in start_thread () from /lib/tls/libpthread.so.0
#10 0x05e613fa in clone () from /lib/tls/libc.so.6

Can you please let me know how can I stop these threads?
Thank you.