Function

CFRunLoopObserverIsValid

Returns a Boolean value that indicates whether a CFRunLoopObserver object is valid and able to fire.

Declaration

Boolean CFRunLoopObserverIsValid(CFRunLoopObserverRef observer);

Parameters

observer

The run loop observer to examine.

Return Value

true if observer is valid, otherwise false.

Discussion

A nonrepeating observer is automatically invalidated after it is called once.

See Also

CFRunLoopObserver Miscellaneous Functions

CFRunLoopObserverCreateWithHandler

Creates a CFRunLoopObserver object with a block-based handler.

CFRunLoopObserverCreate

Creates a CFRunLoopObserver object with a function callback.

CFRunLoopObserverDoesRepeat

Returns a Boolean value that indicates whether a CFRunLoopObserver repeats.

CFRunLoopObserverGetActivities

Returns the run loop stages during which an observer runs.

CFRunLoopObserverGetContext

Returns the context information for a CFRunLoopObserver object.

CFRunLoopObserverGetOrder

Returns the ordering parameter for a CFRunLoopObserver object.

CFRunLoopObserverGetTypeID

Returns the type identifier for the CFRunLoopObserver opaque type.

CFRunLoopObserverInvalidate

Invalidates a CFRunLoopObserver object, stopping it from ever firing again.

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