std::atomic_load, std::atomic_load_explicit

 

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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)(deprecated in C++26) 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>
template<class T > T atomic_load(conststd::atomic<T>* obj )noexcept;	(1)	(since C++11)
template<class T > T atomic_load(constvolatilestd::atomic<T>* obj )noexcept;	(2)	(since C++11)
template<class T > T atomic_load_explicit(conststd::atomic<T>* obj,                         std::memory_order order )noexcept;	(3)	(since C++11)
template<class T > T atomic_load_explicit(constvolatilestd::atomic<T>* obj,                         std::memory_order order )noexcept;	(4)	(since C++11)

1,2) Atomically obtains the value pointed to by obj as if by obj->load().

3,4) Atomically obtains the value pointed to by obj as if by obj->load(order).

If order is one of std::memory_order_release and std::memory_order_acq_rel, the behavior is undefined.

Parameters

obj	-	pointer to the atomic object to modify
order	-	the memory synchronization ordering for this operation

Return value

The value that is held by the atomic object pointed to by obj.

See also

load	atomically obtains the value of the atomic object (public member function of std::atomic<T>)
atomic_storeatomic_store_explicit (C++11)(C++11)	atomically replaces the value of the atomic object with a non-atomic argument (function template)
memory_order (C++11)	defines memory ordering constraints for the given atomic operation (enum)

std::atomic_load(std::shared_ptr)std::atomic_load_explicit(std::shared_ptr) (deprecated in C++20)(removed in C++26)	specializes atomic operations for std::shared_ptr (function template)
C documentation for atomic_load, atomic_load_explicit