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4/8/2010

This function performs an atomic addition of an increment value to an Addendvariable. The function prevents more than one thread from using the same variable simultaneously.

Syntax 

LONG InterlockedExchangeAdd(
  LPLONG 
Addend,
  LONG 
Increment
);

Parameters

Addend

[in, out] Pointer to the number that will have the Incrementnumber added to it.

Increment

[in] Specifies the number to be added to the variable pointed to by the Addendparameter.

Return Value

Initial value of the variable pointed to by the Addendparameter.

Remarks

The InterlockedExchangeAdd, InterlockedCompareExchange, InterlockedDecrement, InterlockedExchange, and InterlockedIncrementfunctions provide a simple mechanism for synchronizing access to a variable that is shared by multiple threads. The threads of different processes can use this mechanism if the variable is in shared memory.

The InterlockedExchangeAddfunction performs an atomic addition of the Incrementvalue to the value pointed to by Addend. The result is stored in the address specified by Addend. The initial value of the variable pointed to by Addendis returned as the function value.

The variables for InterlockedExchangeAddmust be aligned on a 32-bit boundary.

Requirements

Header windows.h
Library coredll.lib
Windows Embedded CE Windows CE .NET 4.0 and later
Windows Mobile Windows Mobile Version 5.0 and later

See Also