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atomic_compare_exchange_weak_explicit Function

Performs a weak atomic compare and exchange operation.

template <class Ty>
inline bool atomic_compare_exchange_weak_explicit(
   volatile atomic<Ty> *Atom,
   Ty *Exp,
   Ty Value,
   memory_order Order1,
   memory_order Order2
) _NOEXCEPT;
template <class Ty>
inline bool atomic_compare_exchange_weak_explicit(
   atomic<Ty> *Atom,
   Ty *Exp,
   Ty Value,
   memory_order Order1,
   memory_order Order2
) _NOEXCEPT;

Parameters

  • Atom
    A pointer to an atomic object that stores a value of type Ty.

  • Exp
    A pointer to a value of type Ty.

  • Value
    A value of type Ty.

  • Order1
    First memory_order argument.

  • Order2
    Second memory_order argument. The value of Order2 cannot be memory_order_release or memory_order_acq_rel, nor can it be stronger than the value of Order1.

Return Value

A bool that indicates the result of the value comparison.

Remarks

An atomic compare and exchange operation compares the value that is stored in the object that is pointed to by Atom with the value that is pointed to by Exp. If the values are equal, the operation replaces the value that is stored in the object that is pointed to by Atom with Val by using a read-modify-write operation and applying the memory-order constraints that are specified by Order1. If the values are not equal, the operation replaces the value that is pointed to by Exp with the value that is stored in the object that is pointed to by Atom and applies the memory-order constraints that are specified by Order2.

A weak atomic compare and exchange operation performs an exchange if the compared values are equal. However, if the values are not equal, the operation is not guaranteed to perform an exchange.

Requirements

Header: atomic

Namespace: std

See Also

Reference

<atomic>

atomic Structure