std::atomic_flag_notify_all

 

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Defined in header <atomic>
		(since C++20)
void atomic_flag_notify_all( std::atomic_flag* object ) noexcept;
void atomic_flag_notify_all( volatile std::atomic_flag* object ) noexcept;

Performs atomic notifying operations.

Unblocks all threads blocked in atomic waiting operations (i.e. std::atomic_flag_wait(), std::atomic_flag_wait_explicit(), or std::atomic_flag::wait()) on *object, if there are any; otherwise does nothing.

Equivalent to object->notify_all().

Parameters

object

-

pointer to the atomic_flag 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_flag)
notify_all (C++20)	notifies all threads blocked waiting on the atomic object (public member function of std::atomic_flag)
atomic_flag_waitatomic_flag_wait_explicit (C++20)(C++20)	blocks the thread until notified and the flag changes (function)
atomic_flag_notify_one (C++20)	notifies a thread blocked in atomic_flag_wait (function)