Don't compare file handles to NULL

Francois Gouget fgouget at
Thu Mar 8 08:25:41 CST 2007

On Thu, 8 Mar 2007, Alexandre Julliard wrote:
> Note that a valid file handle will never be NULL, so while these
> checks are wrong in theory, in practice it makes no difference.

Right. But the invalid check means that in some cases we will call 
CloseHandle(INVALID_HANDLE_VALUE) which the MSDN has this to say about:

> If the application is running under a debugger, the function will 
> throw an exception if it receives either a handle value that is not 
> valid or a pseudo-handle value. This can happen if you close a handle 
> twice, or if you call CloseHandle on a handle returned by the 
> FindFirstFile function.

I did not check but I guess Wine does not do that... so far. It's still 
best avoided.

Francois Gouget <fgouget at>    
The nice thing about meditation is that it makes doing nothing quite respectable
                                  -- Paul Dean

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