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Making an application restartable/rebootable

If you have the need to make an application restartable depending on the user interaction you have to follow these steps:

Create an exit code that represents your reboot/restart event

It is a good idea to define this code as a static variable in your main window:

static int const EXIT_CODE_REBOOT;<code>

and initialize it with a value:

int const MainWindow::EXIT_CODE_REBOOT = ~~123456789;~~

Otherwise you can define a global variable or a constant value.
h3. Define a slot in your application main window that will perform the exit from the application
Define a slot that will exits the application using the reboot code:
void MainWindow::slotReboot() { qDebug() << "Performing application reboot.."; qApp>exit( MainWindow::EXIT_CODE_REBOOT ); }

Create an action to handle the reboot

Create an action that will consume the above slot in order to exit with the reboot code. Something like the following will work:

actionReboot = new QAction( this ); actionReboot->setText( tr("Restart") ); actionReboot->setStatusTip( tr("Restarts the application") ); connect( actionReboot, SIGNAL (triggered()), this, SLOT (slotReboot()) );

Modify the application cycle

The last step is to modify the application main function to handle the new cycle that will allow reboot:

int main(int argc, char *argv[]) { int currentExitCode = 0;

do{ QApplication a(argc, argv); MainWindow w; w.show(); currentExitCode = a.exec&#40;);

}while( currentExitCode == MainWindow::EXIT_CODE_REBOOT );

return currentExitCode;