InterlockedCompareExchange64
InterlockedCompareExchange64 performs an atomic compare-and-exchange operation on the specified values. The function compares two specified 64-bit values and exchanges with another 64-bit value based on the outcome of the comparison.
Syntax
LONGLONG InterlockedCompareExchange64( LONGLONG volatile *Destination, LONGLONG Exchange LONGLONG Comparand );
Parameters
Destination
A pointer to the destination value.
Exchange
The exchange value.
Comparand
The value to compare to Destination.
Return Value
The function returns the initial value of the Destination parameter.
Remarks
The function compares the Destination value with the Comparand value. If the Destination value is equal to the Comparand value, the Exchange value is stored in the address specified by Destination. Otherwise, no operation is performed. The variable pointed to by the Destination parameter must be aligned on a 128-bit boundary.
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 _InterlockedCompareExchange64.
This function generates a full memory barrier (or fence) to ensure that memory operations are completed in order.
Requirements
Minimum Supported Version | RTX64 3.1 |
Header | windows.h |
Library | Rtx_Rtss.lib |
See Also: