Applies to: desktop apps | Metro style apps
Sets a 32-bit variable to the specified value as an atomic operation.
To operate on a pointer variable, use the InterlockedExchangePointer function.
To operate on a 16-bit variable, use the InterlockedExchange16 function.
To operate on a 64-bit variable, use the InterlockedExchange64 function.
Syntax
LONG __cdecl InterlockedExchange( __inout LONG volatile *Target, __in LONG Value );
Parameters
- Target [in, out]
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A pointer to the value to be exchanged. The function sets this variable to Value, and returns its prior value.
- Value [in]
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The value to be exchanged with the value pointed to by Target.
Return value
The function returns the initial value of the Target parameter.
Remarks
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 _InterlockedExchange.
This function generates a full memory barrier (or fence) to ensure that memory operations are completed in order.
Itanium-based systems: For performance-critical applications, use InterlockedExchangeAcquire instead.
Requirements
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Minimum supported client | Windows XP |
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Minimum supported server | Windows Server 2003 |
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Header |
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Library |
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DLL |
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See also
- Interlocked Variable Access
- InterlockedCompareExchange
- InterlockedExchange64
- InterlockedExchangeAcquire
- InterlockedExchangeAdd
- InterlockedExchangePointer
- Synchronization Functions
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Build date: 3/7/2012