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On Thu, Aug 20, 2009 at 07:07:21AM -0600, Eric Blake wrote: >-----BEGIN PGP SIGNED MESSAGE----- >Hash: SHA1 > >According to Dave Korn on 8/20/2009 7:11 AM: >> 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. > >Agreed - Bruno raised this concern, but Paolo committed the change anyway, >so I've asked them to clarify. > >At any rate, Bruno also had this suggestion in that thread: > >static BOOL >IsHandleConsole(HANDLE h) >{ > DWORD mode; > return GetConsoleMode (h, &mode); >} That should be even better than the Cygwin method, assuming that you don't have to figure out if the handle is opened for input or output. cgf -- Problem reports: http://cygwin.com/problems.html FAQ: http://cygwin.com/faq/ Documentation: http://cygwin.com/docs.html Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple
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