Plan 9 from Bell Labs’s /usr/web/sources/contrib/fernan/nhc98/tests/conformance98/layout/tullsen3/Main.hs
import System main = do system("exit 0") >>= printExitCode system("exit 1") >>= printExitCode system("exit 2") >>= printExitCode printExitCode r = case r of ExitSuccess -> print 0 ExitFailure n -> print n