std::atomic_fetch_max,std::atomic_fetch_max_explicit

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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)
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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)

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Defined in header`<atomic>`
template<class T> T atomic_fetch_max(std::atomic<T>* obj, typenamestd::atomic<T>::value_type arg)noexcept;	(1)	(since C++26)
template<class T> T atomic_fetch_max(volatilestd::atomic<T>* obj, typenamestd::atomic<T>::value_type arg)noexcept;	(2)	(since C++26)
template<class T> T atomic_fetch_max_explicit(std::atomic<T>* obj, typenamestd::atomic<T>::value_type arg, std::memory_order order)noexcept;	(3)	(since C++26)
template<class T> T atomic_fetch_max_explicit(volatilestd::atomic<T>* obj, typenamestd::atomic<T>::value_type arg, std::memory_order order)noexcept;	(4)	(since C++26)

Atomically replaces the value pointed byobj with the result ofstd::max between the old value ofobj andarg. Returns the valueobj held previously. The operation is performed as if the following was executed:

1,2)obj->fetch_max(arg)

3,4)obj->fetch_max(arg, order)

Ifstd::atomic<T> has nofetch_max member (this member is only provided forintegral andpointer types exceptbool), the program is ill-formed.

[edit]Parameters

obj	-	pointer to the atomic object to modify
arg	-	the value tostd::max with the value stored in the atomic object
order	-	the memory synchronization ordering

[edit]Return value

The value immediately preceding the effects of this function in themodification order of*obj.

[edit]Notes

Feature-test macro	Value	Std	Feature
`__cpp_lib_atomic_min_max`	`202403L`	(C++26)	Atomic minimum/maximum

[edit]Example

This section is incomplete
Reason: no example

[edit]See also

fetch_max (C++26)	atomically performsstd::max between the argument and the value of the atomic object and obtains the value held previously (public member function of`std::atomic<T>`)[edit]
atomic_fetch_minatomic_fetch_min_explicit (C++26)(C++26)	replaces the atomic object with the result ofstd::min with a non-atomic argument and obtains the previous value of the atomic (function template)[edit]