Returns a Quartz event source created from an existing Quartz event.
- macOS 10.4+
- Mac Catalyst 13.0+
- Core Graphics
The event to access.
An event source created from the specified event, or
NULL if the event was generated with a private event source owned by another process. When you no longer need this event source, you should release it using the function
Event filters may use the event source to generate events that are compatible with an event being filtered.