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GlobalFree info  Overview  Group

The GlobalFree function frees the specified global memory object and invalidates its handle.

HGLOBAL GlobalFree(

    HGLOBAL hMem 

// handle to the global memory object

   );

Parameters

hMem
Identifies the global memory object. This handle is returned by either the GlobalAlloc or GlobalReAlloc function.

Return Values

If the function succeeds, the return value is NULL.

If the function fails, the return value is equal to the handle of the global memory object. To get extended error information, call GetLastError.

Remarks

Heap corruption or an access violation exception (EXCEPTION_ACCESS_VIOLATION) may occur if the process tries to examine or modify the memory after it has been freed.

If the hgblMem parameter is NULL, GlobalFree fails and the system generates an access violation exception.

Both GlobalFree and LocalFree will free a locked memory object. A locked memory object has a lock count greater than zero. The GlobalLock function locks a global memory object and increments the lock count by one. The GlobalUnlock function unlocks it and decrements the lock count by one. To get the lock count of a global memory object, use the GlobalFlags function.

Windows NT: However, if an application is running under a debug (DBG) version of Windows NT, such as the one distributed on the SDK CD-ROM, both GlobalFree and LocalFree enter a breakpoint just before freeing a locked object. This lets a programmer double-check the intended behavior. Typing G while using the debugger in this situation lets the freeing operation occur.

See Also

GlobalAlloc, GlobalFlags, GlobalLock, GlobalReAlloc, GlobalUnlock, LocalFree