I have created a program that is supposed to run a process over and over again, so that the program is restarted as soon as it it finished. Here is the code that handles that:

Qt Code: 
  1. // From process_handler.h
  2. class process_handler : public QObject
  3. {
  4.     Q_OBJECT
  5.  
  6. public:
  7.     process_handler();
  8.  
  9. private:
  11.  
  12. public slots:
  13.     void start_process();
  14.  
  15. private slots:
  16.     void process_state_changed();
  17. };
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Qt Code: 
  1. // From process_handler.cpp
  2. process_handler::process_handler()
  3. {
  4.     connect(&p, SIGNAL(stateChanged(QProcess::ProcessState)), this, SLOT(process_state_changed()));
  5. }
  6.  
  7. void process_handler::process_state_changed()
  8. {
  9.     if (p.state() == QProcess::Starting) {
  10.         cout << endl;
  11.         cout << "Process is starting up..." << endl;
  12.     }
  13.     if (p.state() == QProcess::Running) {
  14.         cout << "Process is now running." << endl;
  15.     }
  16.     if (p.state() == QProcess::NotRunning) {
  17.         cout << "Process is finished running." << endl;
  18.  
  19.         /* Start a new process */
  20.         //start_process();
  21.         QTimer::singleShot(0, this, SLOT(start_process()));
  22.     }
  23. }
  24.  
  25. void process_handler::start_process()
  26. {
  27.     p.start("program");
  28. }
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"program" is a program that takes a few seconds to run and thex terminates. As you see I have used a QTimer::singleShot to call start_process() from process_state_changed(). If I don't use it, but call start_process() directly, the text

Qt Code: 
  1. Process is starting up...
  2. Process is now running.
  3. Process is finished running.
  4.  
  5. Process is starting up...
  6. Process is now running.
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is written to cout and then I get a segmentation fault. Does anyone know why this segmentation fault occurs? I would like it if I didn't have to use a singleShot, since that will make coding much more complicated later on.