| Defined in header |
C atomic_exchange( volatile A* obj, C desired );
C atomic_exchange_explicit( volatile A* obj, C desired, memory_order order );
Atomically replaces the value pointed by
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
This is a generic function defined for all atomic object types
A. The argument is pointer to a volatile atomic type to accept addresses of both non-volatile and volatile (e.g. memory-mapped I/O) atomic objects, and volatile semantic is preserved when applying this operation to volatile atomic objects.
C is the non-atomic type corresponding to
It is unspecified whether the name of a generic function is a macro or an identifier declared with external linkage. If a macro definition is suppressed in order to access an actual function (e.g. parenthesized like
(atomic_exchange)(...)), or a program defines an external identifier with the name of a generic function, the behavior is undefined..
|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|
The value held previously be the atomic object pointed to by
| swaps a value with an atomic object if the old value is what is expected, otherwise reads the old value
| C++ documentation for
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