This morning my attention was grabbed by an old post in the Apple Developer Forums, bemoaning the appearance of NSAlert in Big Sur. I filed FB9960090: “CoreVideo logging should default to 0”, requesting that Apple change the behavior of this initialization function so that if a user has not set the cv_note value to anything particular, it defaults to 0. Within that function, there is a call to another function called “cv_note_init_logging_once”, and within that is a check for a user default value along with this tasty morsel:Īnd thank you, Apple, for providing such a mechanism, even if it’s unfortunately configured to log by default.

After setting a breakpoint early in my app’s launch, I set a breakpoint on a variety of logging related methods until I discovered that these messages are all originating from a function called cv_note() in the CoreVideo framework. I discovered this user default by spelunking the system frameworks code from which they originate. The only downside to disabling the messages globally is that you will have to remember you disabled it if you ever decide you want to see massive quantities of Core Video debugging logs! Alternatively, you could disable them across all of your apps by setting this global default:ĭefaults write cv_note 0

Just pass “-cv_note 0” as a parameter to the Run task in the Xcode scheme.

Today I went digging to find the source of these log messages, and in the process I discovered a workaround that disables them. In recent months I’ve noticed an accumulation of garbage log messages when I’m debugging an app in Xcode.

Automator mac hack