http://bugs.winehq.org/show_bug.cgi?id=5163
--- Comment #50 from Dan Kegel dank@kegel.com 2008-04-13 18:54:43 --- 5 is fdintENUMERATE, which is undocumented. It's described a little bit in our doc for FDICopy: http://source.winehq.org/WineAPI/FDICopy.html