if (key->data == NULL || key->size == 0) return (__db_keyempty(dbp->dbenv));
__db_delchk(dbp, flags, isrdonly)	const DB *dbp;	int flags, isrdonly;{	/* Check for changes to a read-only tree. */	if (isrdonly)		return (__db_rdonly(dbp->dbenv, "delete"));	/* Check for invalid db->del() function flags. */	DB_CHECK_FLAGS(dbp->dbenv, "delete", flags, 0);	return (0);}