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std::atomic<T>::fetch_or

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< cpp‎ | atomic‎ | atomic

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atomic::operator++atomic::operator++(int)atomic::operator--atomic::operator--(int)

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atomic::fetch_or

atomic::fetch_xor

atomic::operator&=atomic::operator|=atomic::operator^=

member only of atomic<Integral > specializations

T fetch_or( T arg, std::memory_order order =
std::memory_order_seq_cst ) noexcept;

(1) (since C++11)

T fetch_or( T arg, std::memory_order order =
std::memory_order_seq_cst ) volatile noexcept;

(2) (since C++11)

Atomically replaces the current value with the result of bitwise OR of the value and arg. The operation is read-modify-write operation. Memory is affected according to the value of order.

It is deprecated if std::atomic <T>::is_always_lock_free is false and overload (2) participates in overload resolution.

(since C++20)

[edit] Parameters

arg - the other argument of bitwise OR

order - memory order constraints to enforce

[edit] Return value

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

[edit] See also

atomic_fetch_oratomic_fetch_or_explicit

(C++11)(C++11)

replaces the atomic object with the result of bitwise OR with a non-atomic argument and obtains the previous value of the atomic
(function template) [edit]

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