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4/8/2010

This function atomically exchanges a pair of 32-bit values.

Syntax 

LONG InterlockedExchange(
  LPLONG 
Target,
  LONG 
Value
);

Parameters

Target

[in] Pointer to the LONGvalue to exchange. The function sets this LONGvalue to Value, and returns its prior value.

Value

[in] Specifies a new value for the LONGvalue pointed to by Target.

Return Value

The prior value of the LONGvalue pointed to by Targetindicates success.

Remarks

The functions InterlockedExchange, InterlockedCompareExchange, InterlockedDecrement, InterlockedExchangeAdd, and InterlockedIncrementprovide 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 variable pointed to by the Targetparameter must be aligned on a 32-bit boundary; otherwise, this function will fail.

Requirements

Header winbase.h
Library coredll.lib
Windows Embedded CE Windows CE 1.0 and later
Windows Mobile Windows Mobile Version 5.0 and later

See Also