extern int open_mddev(char *dev, int autof);
extern int open_mddev_devnum(char *devname, int devnum, char *name,
char *chosen_name, int parts);
extern int open_mddev(char *dev, int autof);
extern int open_mddev_devnum(char *devname, int devnum, char *name,
char *chosen_name, int parts);