std::atomic_fetch_min, std::atomic_fetch_min_explicit

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< cpp‎ | atomic
 
 
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atomic_fetch_minatomic_fetch_min_explicit
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Defined in header <atomic>
template< class T >

T atomic_fetch_min( std::atomic<T>* obj,

                    typename std::atomic<T>::value_type arg ) noexcept;
(1) (since C++26)
template< class T >

T atomic_fetch_min( volatile std::atomic<T>* obj,

                    typename std::atomic<T>::value_type arg ) noexcept;
(2) (since C++26)
template< class T >

T atomic_fetch_min_explicit( std::atomic<T>* obj,
                             typename std::atomic<T>::value_type arg,

                             std::memory_order order ) noexcept;
(3) (since C++26)
template< class T >

T atomic_fetch_min_explicit( volatile std::atomic<T>* obj,
                             typename std::atomic<T>::value_type arg,

                             std::memory_order order ) noexcept;
(4) (since C++26)

Atomically replaces the value pointed by obj with the result of std::min between the old value of obj and arg. Returns the value obj held previously. The operation is performed as if the following was executed:

1,2) obj->fetch_min(arg)
3,4) obj->fetch_min(arg, order)

If std::atomic<T> has no fetch_min member (this member is only provided for integral and pointer types except bool), the program is ill-formed.

Parameters

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

Return value

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

Notes

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

Example

See also

(C++26)
atomically performs std::min between the argument and the value of the atomic object and obtains the value held previously
(public member function of std::atomic<T>)
replaces the atomic object with the result of std::max with a non-atomic argument and obtains the previous value of the atomic
(function template)