NSNotificationCenter trapping and tracing all NSNotifications

Question

For some better understanding on what happens “under the hood”, I would love to do a complete trace of any notifications happening within my application.

Naïve as I

Answer 1

@Till solution in Swift 5.0 & Xcode 11:

CFNotificationCenterAddObserver(
    CFNotificationCenterGetLocalCenter(),
    nil,
    { (notificationCenter, _, notificationName, _, dictionary) in
        print(notificationName)
        print(dictionary)
}, nil, nil, .deliverImmediately)