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4/8/2010

This function both decrements the value of the specified 32-bit variable and checks the resulting value. InterlockedDecrementprevents more than one thread from using the InterlockedDecrementfunction or InterlockedIncrementfunction to access the same variable simultaneously.

Syntax 

LONG InterlockedDecrement(
  LPLONG 
lpAddend
);

Parameters

lpAddend

[in] Pointer to the 32-bit variable to decrement.

Return Value

Decremented value.

Remarks

The functions InterlockedDecrement, InterlockedCompareExchange, InterlockedExchange, InterlockedExchangeAdd, and InterlockedIncrementprovide 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 lpAddendparameter must be aligned on a 32-bit boundary.

Requirements

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

See Also