Resumes the invocation of block objects on a dispatch object.


void dispatch_resume(dispatch_object_t object);



The object to be resumed. This parameter cannot be NULL.


Calling this function decrements the suspension count of a suspended dispatch queue or dispatch event source object. While the count is greater than zero, the object remains suspended. When the suspension count returns to zero, any blocks submitted to the dispatch queue or any events observed by the dispatch source while suspended are delivered.

With one exception, each call to dispatch_resume must balance a call to dispatch_suspend. New dispatch event source objects returned by dispatch_source_create have a suspension count of 1 and must be resumed before any events are delivered. This approach allows your application to fully configure the dispatch event source object prior to delivery of the first event. In all other cases, it is undefined to call dispatch_resume more times than dispatch_suspend, which would result in a negative suspension count.

See Also

Activating, Suspending, and Resuming the Object


Activates the dispatch object.


Suspends the invocation of block objects on a dispatch object.


A dispatch object.

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