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InterlockedDecrementAcquire64 function

Decrements (decreases by one) the value of the specified 64-bit variable as an atomic operation. The operation is performed with acquire memory ordering semantics.

Syntax

LONGLONG __cdecl InterlockedDecrementAcquire64(
  _Inout_ LONGLONG volatile *Addend
);

Parameters

  • Addend [in, out]
    A pointer to the variable to be decremented.

Return value

The function returns the resulting decremented value.

Remarks

The variable pointed to by the Addend parameter must be aligned on a 64-bit boundary; otherwise, this function will behave unpredictably on multiprocessor x86 systems and any non-x86 systems. See _aligned_malloc.

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 _InterlockedDecrement64_acq.

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

 

Requirements

Header

Winnt.h (include Windows.h)

See also

Interlocked Variable Access

InterlockedDecrement

InterlockedDecrementAcquire

InterlockedDecrementRelease

InterlockedDecrementNoFence

InterlockedDecrement16

InterlockedDecrement16Acquire

InterlockedDecrement16Release

InterlockedDecrement16NoFence

InterlockedDecrement64

InterlockedDecrementRelease64

InterlockedDecrementNoFence64

Synchronization Functions