extern int umoven P((struct tcb *, long, int, char *));
extern int umovestr P((struct tcb *, long, int, char *));
extern int upeek P((int, long, long *));
extern int umoven P((struct tcb *, long, int, char *));
extern int umovestr P((struct tcb *, long, int, char *));
extern int upeek P((int, long, long *));