extern int io_peek(struct iop *, char *, int);
extern int io_read(struct iop *, char *, int);
extern int io_write(struct iop *, char *, int);
extern int io_gets(struct iop *, char *, int);
extern int io_puts(struct iop *, char *);
extern int io_peek(struct iop *, char *, int);
extern int io_read(struct iop *, char *, int);
extern int io_write(struct iop *, char *, int);
extern int io_gets(struct iop *, char *, int);
extern int io_puts(struct iop *, char *);