InterlockedExchangePointerNoFence function
Atomically exchanges a pair of addresses. The operation is performed atomically, but without using memory barriers.
Syntax
void* __cdecl InterlockedExchangePointerNoFence(
_Inout_ void volatile *Target,
_In_ void *Value
);
Parameters
Target [in, out]
A pointer to the address to exchange. The function sets the address pointed to by the Target parameter (*Target) to the address that is the value of the Value parameter, and returns the prior value of the Target parameter.Value [in]
The address to be exchanged with the address pointed to by the Target parameter (*Target).
Return value
The function returns the initial address pointed to by the Target parameter.
Remarks
This function copies the address passed as the second parameter to the first and returns the original address of the first.
On a 64-bit system, the parameters are 64 bits and the Target parameter must be aligned on 64-bit boundaries; otherwise, the function will behave unpredictably. On a 32-bit system, the parameters are 32 bits and the Target parameter must be aligned on 32-bit boundaries. On a 16-bit system, the parameters are 16 bits and the Target parameter must be aligned on 32-bit boundaries.
The interlocked functions provide a simple mechanism for synchronizing access to a variable that is shared by multiple threads. This function is atomic with respect to calls to other interlocked functions.
This function is implemented using a compiler intrinsic where possible. For more information, see the WinBase.h header file and _InterlockedExchangePointer_nf.
This function generates no memory barriers (or fences) and does not guarantee that independent memory operations before or after it are completed in order.
Note This function is supported on Windows RT-based systems.
Requirements
Minimum supported client |
Windows 8 [desktop apps only] |
Minimum supported server |
Windows Server 2012 [desktop apps only] |
Header |
Winnt.h (include Windows.h) |