beforeWaiting
Declaration
static var beforeWaiting: CFRunLoopActivity { get }Discussion
Inside the event processing loop before the run loop sleeps, waiting for a source or timer to fire. This activity does not occur if CFRunLoopRunInMode(_:_:_:) is called with a timeout of 0 seconds. It also does not occur in a particular iteration of the event processing loop if a version 0 source fires.