(* Process *) type status = int val success : status = 0; #if defined(win32)val failure : status = 1;#elseval failure : status = ~1;#endif prim_val system : string -> status = 1 "sml_system"; local    prim_val getenv_ : string -> string = 1 "sys_getenv";in    fun getEnv s = 	(SOME (getenv_ s)) handle _ => NONEend val terminate = BasicIO.exit; local     val exittasks = (ref []) : (unit -> unit) list refin     fun atExit newtask =	exittasks := newtask :: !exittasks;    fun exit status =	(List.app (fn f => f ()) (!exittasks);	terminate status);end