std::atomic_notify_one

 

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Defined in header <atomic>
		(since C++20)
template< class T > void atomic_notify_one( std::atomic<T>* object );
template< class T > void atomic_notify_one( volatile std::atomic<T>* object );

Performs atomic notifying operations.

If there is a thread blocked in atomic waiting operation (i.e. std::atomic_wait(), std::atomic_wait_explicit(), or std::atomic::wait()) on *object, then unblocks at least one such thread; otherwise does nothing.

Equivalent to object->notify_one().

Parameters

object

-

pointer to the atomic object to notify

Return value

(none)

Notes

This form of change-detection is often more efficient than simple polling or pure spinlocks.

See also

notify_one (C++20)	notifies at least one thread waiting on the atomic object (public member function of std::atomic<T>)
notify_all (C++20)	notifies all threads blocked waiting on the atomic object (public member function of std::atomic<T>)
atomic_notify_all (C++20)	notifies all threads blocked in atomic_wait (function template)
atomic_waitatomic_wait_explicit (C++20)(C++20)	blocks the thread until notified and the atomic value changes (function template)