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)
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Memory ordering
memory_order (C++11)
kill_dependency (C++11)
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Free functions for atomic operations
atomic_store atomic_store_explicit (C++11) (C++11)
atomic_load atomic_load_explicit (C++11) (C++11)
atomic_exchange atomic_exchange_explicit (C++11) (C++11)
atomic_compare_exchange_weak atomic_compare_exchange_weak_explicit atomic_compare_exchange_strong atomic_compare_exchange_strong_explicit (C++11) (C++11) (C++11) (C++11)
atomic_fetch_add atomic_fetch_add_explicit (C++11) (C++11)
atomic_fetch_sub atomic_fetch_sub_explicit (C++11) (C++11)
atomic_fetch_and atomic_fetch_and_explicit (C++11) (C++11)
atomic_fetch_or atomic_fetch_or_explicit (C++11) (C++11)
atomic_fetch_xor atomic_fetch_xor_explicit (C++11) (C++11)
atomic_fetch_max atomic_fetch_max_explicit (C++26) (C++26)
atomic_fetch_min atomic_fetch_min_explicit (C++26) (C++26)
atomic_is_lock_free (C++11)
atomic_wait atomic_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_set atomic_flag_test_and_set_explicit (C++11) (C++11)
atomic_flag_clear atomic_flag_clear_explicit (C++11) (C++11)
atomic_flag_test atomic_flag_test_explicit (C++20) (C++20)
atomic_flag_wait atomic_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 ( const std:: atomic < T > * obj ) noexcept ;	(1)	(since C++11)
template < class T > T atomic_load ( const volatile std:: atomic < T > * obj ) noexcept ;	(2)	(since C++11)
template < class T > T atomic_load_explicit ( const std:: atomic < T > * obj, std:: memory_order order ) noexcept ;	(3)	(since C++11)
template < class T > T atomic_load_explicit ( const volatile std:: 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 .

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External libraries

std:: atomic_load, std:: atomic_load_explicit

Parameters

Return value

See also

Navigation

load	atomically obtains the value of the atomic object (public member function of `std::atomic<T>` )
atomic_store atomic_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