extern struct group *__gr_dup(const struct group *);
extern void __gr_set_changed(void);
extern int gr_close(void);
extern const struct group *gr_locate(const char *);
extern int gr_lock(void);
extern int gr_name(const char *);
extern const struct group *gr_next(void);
extern int gr_open(int);
extern int gr_remove(const char *);
extern int gr_rewind(void);
extern int gr_unlock(void);
extern int gr_update(const struct group *);