Hi All, Just to wrap this up: thanks everybody for their results, it has been useful. The luatex trunk now has support for os.uname(), also under Windows. Some people may find it interesting to see the outcome of this mini-survey. Here is a tally of what I received from various people, besides my own Linux/i386-es, and Hans' Windows Vista/i686: 1 CYGWIN_NT-5.1/i686 6 Darwin/i386 2 Darwin/Power Macintosh 1 FreeBSD/amd64 1 FreeBSD/i386 1 HP-UX/ia64 1 IRIX64/IP27 1 IRIX/IP32 1 Linux/i686 2 Linux/ppc 1 Linux/ppc64 2 Linux/sparc64 5 Linux/x86_64 1 OpenBSD/i386 1 OpenVMS/HP_rx2600__(1.40GHz/1.5MB) 2 SunOS/sun4u Best wishes, Taco