InterlockedExchange

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4/8/2010

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

Syntax

LONG InterlockedExchange(
  LPLONG Target,
  LONG Value
);

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

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

The prior value of the LONG value pointed to by Target indicates success.

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

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