#define listenToNotification$withCallBack(notification, callback)   \
CFNotificationCenterAddObserver(CFNotificationCenterGetDarwinNotifyCenter(), \
self, \
&callback, \
CFSTR(notification), \
NULL, \
CFNotificationSuspensionBehaviorHold);

//example:
listenToNotification$withCallBack("com.homeschooldev.enabledswitch", &callback)
static void callback(CFNotificationCenterRef center, void *observer, CFStringRef name, const void *object, CFDictionaryRef userInfo) {

}