__bt_close
dbp->close = __bt_close;
int __bt_close __P((DB *));
if (__bt_close(dbp) == RET_ERROR)
(void)__bt_close(dbp);
dbp->close = __bt_close;
int __bt_close(DB *);
if (__bt_close(dbp) == RET_ERROR)
(void)__bt_close(dbp);