dbm_firstkey
key = dbm_firstkey(d->db);
#define dbm_firstkey dbm_rename(dbm_firstkey)
ROKEN_LIB_FUNCTION datum ROKEN_LIB_CALL dbm_firstkey (DBM*);
datum dbm_firstkey __P((DBM *));
datum dbm_firstkey(DBM *);
key = dbm_firstkey(db);