std::atomic_flag_notify_one

 

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Atomic types atomic (C++11) atomic_ref (C++20) atomic_flag (C++11) Initialization of atomic types atomic_init (C++11)(deprecated in C++20) ATOMIC_VAR_INIT (C++11)(deprecated in C++20) ATOMIC_FLAG_INIT (C++11) Memory ordering memory_order (C++11) kill_dependency (C++11) atomic_thread_fence (C++11) atomic_signal_fence (C++11) Free functions for atomic operations atomic_storeatomic_store_explicit (C++11)(C++11) atomic_loadatomic_load_explicit (C++11)(C++11) atomic_exchangeatomic_exchange_explicit (C++11)(C++11) atomic_compare_exchange_weakatomic_compare_exchange_weak_explicitatomic_compare_exchange_strongatomic_compare_exchange_strong_explicit (C++11)(C++11)(C++11)(C++11) atomic_fetch_addatomic_fetch_add_explicit (C++11)(C++11) atomic_fetch_subatomic_fetch_sub_explicit (C++11)(C++11) atomic_fetch_andatomic_fetch_and_explicit (C++11)(C++11) atomic_fetch_oratomic_fetch_or_explicit (C++11)(C++11) atomic_fetch_xoratomic_fetch_xor_explicit (C++11)(C++11) atomic_fetch_maxatomic_fetch_max_explicit (C++26)(C++26) atomic_fetch_minatomic_fetch_min_explicit (C++26)(C++26) atomic_is_lock_free (C++11) atomic_waitatomic_wait_explicit (C++20)(C++20) atomic_notify_one (C++20) atomic_notify_all (C++20) Free functions for atomic flags atomic_flag_test_and_setatomic_flag_test_and_set_explicit (C++11)(C++11) atomic_flag_clearatomic_flag_clear_explicit (C++11)(C++11) atomic_flag_testatomic_flag_test_explicit (C++20)(C++20) atomic_flag_waitatomic_flag_wait_explicit (C++20)(C++20) atomic_flag_notify_one (C++20) atomic_flag_notify_all (C++20)

 

Defined in header <atomic>
void atomic_flag_notify_one( std::atomic_flag* object ) noexcept;	(1)	(since C++20)
void atomic_flag_notify_one( volatile std::atomic_flag* object ) noexcept;	(2)	(since C++20)

Performs atomic notifying operations.

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

Equivalent to object->notify_one().

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_notify_all (C++20)	notifies all threads blocked in atomic_flag_wait (function)