Increments the reference count (the retain count) of a dispatch object.
- iOS 4.0+
- macOS 10.6+
- tvOS 9.0+
- watchOS 2.0+
The object to retain. This parameter cannot be
Calls to this function must be balanced with calls to
dispatch. If multiple subsystems of your application share a dispatch object, each subsystem should call
dispatch to register its interest in the object. The object is deallocated only when all subsystems have released their interest in the dispatch source.
Note that your application does not need to retain or release the global (main and concurrent) dispatch queues.