'Stops the scanning.'

def _scan_stop(self):

    def stop_scan_wrap():
        try:
            self.w3af.stop()
        except Exception:
            plugins_str = pprint_plugins(self.w3af)
            (exc_class, exc_inst, exc_tb) = sys.exc_info()
            unhandled.handle_crash(self.w3af, exc_class, exc_inst, exc_tb, plugins=plugins_str)
    scan_stop = Process(target=stop_scan_wrap, name='ScanStopper')
    scan_stop.daemon = True
    scan_stop.start()
    self.startstopbtns.set_sensitive(False)
    self.toolbut_pause.set_sensitive(False)
    self.sb(_('Stopping    the    scan...'), 15)
    self.stopped_by_user = True
