InterlockedDecrement
The InterlockedDecrement
function both decrements (decreases by one) the value of the specified 32-bit
variable and checks the resulting value. The function prevents more than one
thread from using the same variable simultaneously.
LONG InterlockedDecrement(
|
LPLONG lpAddend |
// address of the
variable to decrement |
|
); |
|
Parameters
lpAddend
Points to the
32-bit variable to decrement.
Return Values
If the result
of the decrement is zero, the return value is zero.
If the result
of the decrement is less than zero, the return value is less than zero. If the
result of the decrement is greater than zero, the return value is greater than
zero. A nonzero return value may not be equal to the result of the decrement.
Remarks
The functions
InterlockedDecrement, InterlockedCompareExchange, InterlockedExchange,
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 lpAddend parameter must be aligned on a 32-bit
boundary; otherwise, this function will fail on multiprocessor x86
systems.
See Also