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std::atomic_flag:: notify_one

From cppreference.net

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std::atomic_flag
void notify_one ( ) noexcept ;
(1) (since C++20)
(constexpr since C++26)
void notify_one ( ) volatile noexcept ;
(2) (since C++20)

Performs atomic notifying operations.

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

Notes

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

Example

This section is incomplete
Reason: no example

See also

(C++20)
blocks the thread until notified and the atomic value changes
(public member function)
(C++20) (C++20)
blocks the thread until notified and the flag changes
(function)
(C++20)
notifies a thread blocked in atomic_flag_wait
(function)