NAME

std::atomic::fetch_or - std::atomic::fetch_or

Synopsis

T fetch_or( T arg,
std::memory_order order = (since C++11)
std::memory_order_seq_cst ) noexcept; (member only of atomic<Integral>
T fetch_or( T arg, template specialization)
std::memory_order order =
std::memory_order_seq_cst ) volatile noexcept;

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.

The volatile-qualified version is deprecated if (since C++20)
std::atomic<T>::is_always_lock_free is false.

Parameters

arg - the other argument of bitwise OR
order - memory order constraints to enforce

Return value

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

See also

atomic_fetch_or replaces the atomic object with the result of bitwise OR
atomic_fetch_or_explicit with a non-atomic argument and obtains the previous value
(C++11) of the atomic
(C++11) (function template)