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Date: Thu, 20 Aug 2009 14:11:06 +0100
From: Dave Korn <dave DOT korn DOT cygwin AT googlemail DOT com>
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Eric Blake wrote:

> See this thread on the gnulib list, which claims that you can use this
> undocumented snippet to decide whether a HANDLE is a console:
> 
>> #define IsHandleConsole(h) (((long) (h) & 3) == 3)
> 
> http://lists.gnu.org/archive/html/bug-gnulib/2009-08/msg00065.html

  I wouldn't rely on that for a microsecond.  The low two bits of a HANDLE are
pretty free form and could easily be used for other purposes by other types of
object.  Read the rest of the thread; it's a convention used internally by
WINE.  MS doesn't necessarily follow suit.  See also Chen on handles:

http://blogs.msdn.com/oldnewthing/archive/2005/01/21/358109.aspx

    cheers,
      DaveK


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