InterlockedExchangeAcquire function

Sets a 32-bit variable to the specified value as an atomic operation. The operation is performed using acquire memory ordering semantics.

Syntax

C++


LONG __cdecl InterlockedExchangeAcquire(
  _Inout_ LONG volatile *Target,
  _In_    LONG          Value
);

Parameters

Target [in, out]: A pointer to the value to be exchanged. The function sets this variable to Value, and returns its prior value.
Value [in]: 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_acq.

This function is supported only on Itanium-based systems.

Note Windows 8 does not support Itanium-based systems.

Note This function is supported on Windows RT-based systems.

Note

Requirements

Header	Winnt.h (include Windows.h)