std::atomic_store, std::atomic_store_explicit

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Mutual exclusion

mutex (C++11)
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lock (C++11)
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unique_lock (C++11)
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try_lock (C++11)
defer_locktry_to_lockadopt_lockdefer_lock_ttry_to_lock_tadopt_lock_t (C++11) (C++11) (C++11) (C++11) (C++11) (C++11)

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(C++11)

cv_status

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counting_semaphorebinary_semaphore

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(C++20)

(C++20)

promise (C++11)
future (C++11)
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launch (C++11)
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Safe Reclamation

rcu_obj_base (C++26)
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rcu_default_domain (C++26)

rcu_synchronize (C++26)
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Hazard Pointers

hazard_pointer_obj_base

(C++26)

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(C++26)

make_hazard_pointer

(C++26)

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>`
template < class T > void atomic_store( std::atomic <T> * obj, typename std::atomic <T> :: value_type desired ) noexcept ;	(1)	(since C++11)
template < class T > void atomic_store( volatile std::atomic <T> * obj, typename std::atomic <T> :: value_type desired ) noexcept ;	(2)	(since C++11)
template < class T > void atomic_store_explicit( std::atomic <T> * obj, typename std::atomic <T> :: value_type desired, std::memory_order order) noexcept ;	(3)	(since C++11)
template < class T > void atomic_store_explicit( volatile std::atomic <T> * obj, typename std::atomic <T> :: value_type desired, std::memory_order order) noexcept ;	(4)	(since C++11)

1,2) Atomically replaces the value pointed to by obj with the value of desired as if by obj->store(desired)

3,4) Atomically replaces the value pointed to by obj with the value of desired as if by obj->store(desired, order)

If order is one of std::memory_order_consume, std::memory_order_acquire and std::memory_order_acq_rel

Parameters

obj	-	pointer to the atomic object to modify
desired	-	the value to store in the atomic object
order	-	the memory synchronization ordering

Return value

(none)

Defect reports

The following behavior-changing defect reports were applied retroactively to previously published C++ standards.

DR	Applied to	Behavior as published	Correct behavior
P0558R1	C++11	exact type match was required because `T` was deduced from multiple arguments	`T` is only deduced from obj

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External libraries

std::atomic_store, std::atomic_store_explicit

Parameters

Return value

Defect reports

See also

Navigation

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

std::atomic_store(std::shared_ptr) std::atomic_store_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_store, atomic_store_explicit