std::atomic_ref<T>:: fetch_sub
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| Member functions | ||||
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(C++26)
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| Constants | ||||
| Specialized member functions | ||||
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Specialized for integral,
floating-point and pointer types |
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atomic_ref::fetch_sub
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Specialized for integral and
pointer types only |
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(C++26)
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(C++26)
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| Specialized for integral types only | ||||
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member only of
atomic_ref<
Integral
>
and
atomic_ref<
Floating
>
template specializations
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T fetch_sub
(
T arg,
std:: memory_order order = std:: memory_order_seq_cst ) const noexcept ; |
(1) | (since C++20) |
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member only of
atomic_ref<T*>
template specialization
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T
*
fetch_sub
(
std::
ptrdiff_t
arg,
std:: memory_order order = std:: memory_order_seq_cst ) const noexcept ; |
(2) | (since C++20) |
Atomically replaces the current value of the referenced object with the result of arithmetic subtraction of the value and arg . This operation is a read-modify-write operation. Memory is affected according to the value of order .
For signed integral types, arithmetic is defined to use two’s complement representation. There are no undefined results.
For floating-point types, the floating-point environment in effect may be different from the calling thread's floating-point environment. The operation need not be conform to the corresponding std::numeric_limits traits but is encouraged to do so. If the result is not a representable value for its type, the result is unspecified but the operation otherwise has no undefined behavior.
For
T*
types, the result may be an undefined address, but the operation otherwise has no undefined behavior. The program is ill-formed if
T
is not an object type.
Parameters
| arg | - | the other argument of arithmetic subtraction |
| order | - | memory order constraints to enforce |
Return value
The value of the referenced object, immediately preceding the effects of this function.
Example
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This section is incomplete
Reason: no example |