InterlockedExchangeAdd

InterlockedExchangeAdd performs an atomic addition of two 64-bit values.

Syntax

Copy
LONG InterlockedExchangeAdd(
      LONG  volatile     *Addend,
      LONG                Value  
);

Parameters

Addend

A pointer to a variable. The value of this variable will be replaced with the result of the operation.

Value

The value to be added to the variable pointed to by the Addend parameter.

Return Value

The function returns the initial value of the Addend parameter.

Remarks

The function performs an atomic addition of Value to the value pointed to by Addend. The result is stored in the address specified by Addend. The function returns the initial value of the variable pointed to by Addend.

The variables for this function must be aligned on a 64-bit boundary; otherwise, this function will behave unpredictably. See _aligned_malloc.

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 _InterlockedExchangeAdd

This function generates a full memory barrier (or fence) to ensure that memory operations are completed in the proper sequence.

To operate on 64-bit values, use the InterlockedExchangeAdd64 function.

Requirements

Minimum supported version Header Library

eRTOS 1.0 SDK

windows.h

rtkrnl.lib

See Also: