module System import Data.So %cg chicken (use posix) exportsleep : Int -> IO ()sleep sec = schemeCall () "blodwen-sleep" [sec] exportusleep : (x : Int) -> So (x >= 0) => IO ()usleep usec = schemeCall () "blodwen-usleep" [usec] exportgetArgs : IO (List String)getArgs = schemeCall (List String) "blodwen-args" [] %foreign "scheme:getenv"prim_getEnv : String -> PrimIO String %foreign "scheme:blodwen-hasenv"prim_hasEnv : String -> PrimIO Int exportgetEnv : String -> IO (Maybe String)getEnv var   = do ok <- primIO $ prim_hasEnv var        if ok == 0           then pure Nothing           else map pure $ primIO (prim_getEnv var) %foreign "scheme:blodwen-system"prim_system : String -> PrimIO Int exportsystem : String -> IO Intsystem cmd = primIO (prim_system cmd) exporttime : IO Integertime = schemeCall Integer "blodwen-time" []