atomic_exchange, atomic_exchange_explicit
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                    | Defined in header  <stdatomic.h> | ||
| C atomic_exchange( volatile A* obj, C desired ); | (1) | (since C11) | 
| C atomic_exchange_explicit( volatile A* obj, C desired, memory_order order ); | (2) | (since C11) | 
Atomically replaces the value pointed by obj with desired and returns the value obj held previously. The operation is read-modify-write operation. The first version orders memory accesses according to memory_order_seq_cst, the second version orders memory accesses according to order. 
This is a generic function defined for all atomic object types. A is the type of an atomic object, C is the non-atomic type corresponding to A.
[edit] Parameters
| obj | - | pointer to the atomic object to modify | 
| desired | - | the value to replace the atomic object with | 
| order | - | the memory synchronization ordering for this operation: all values are permitted | 
[edit] Return value
The value held previously be the atomic object pointed to by obj.
[edit] See also
| swaps a value with the an atomic object if the old value is what is expected, otherwise reads the old value (function) | |
| C++ documentation for atomic_exchange, atomic_exchange_explicit | |


