Hogyúgyvan :)
$ uname.exe -a ; echo; gcc -ansi -Dunix -Wall korn.c -o korn.exe ; echo; ./korn.exe
CYGWIN_NT-5.1 mazsola 1.7.6(0.230/5/3) 2010-08-16 16:06 i686 Cygwin
korn.c:1: warning: return type defaults to `int'
korn.c: In function `main':
korn.c:1: warning: implicit declaration of function `printf'
korn.c:1: warning: embedded `\0' in format
korn.c:1: warning: control reaches end of non-void function
unix