Problems on accessing Windows network resources

Corinna Vinschen cygwin-patches@cygwin.com
Sat Jul 12 15:57:00 GMT 2003


On Sat, Jul 12, 2003 at 09:37:37AM -0400, Pierre A. Humblet wrote:
> At 10:31 AM 7/12/2003 +0200, Corinna Vinschen wrote:
> 
> >thanks for the patch but it has a problem.  You're comparing tokens against
> >NULL while the correct "NULL" value for tokens is INVALID_HANDLE_VALUE. 
> 
> Corinna,
> 
> That's by design, using of Chris' astute observations. As he once
> pointed out, INVALID_HANDLE_VALUE is the value returned in case of error
> but NULL is not a legal handle value either, as implied by CreateFile
> itself. Microsoft is using NULL handle values all the time. For the 
> specific case of a NULL token handle, see SetThreadToken.

What I don't like is that tokens can get both values now.  Most of the
time they are initialized to INVALID_HANDLE_VALUE, your code introduces
additionally NULL values.  At one point we will suddenly get a problem
because a `if (!foo_token)' doesn't handle the INVALID_HANDLE_VALUE case.

Regardless if INVALID_HANDLE_VALUE or NULL is the correct value, I want
to see only one of them used in Cygwin internally.


Corinna

-- 
Corinna Vinschen                  Please, send mails regarding Cygwin to
Cygwin Developer                                mailto:cygwin@cygwin.com
Red Hat, Inc.



More information about the Cygwin-patches mailing list