Oracle cursor type as input and output parameters

Oracle cursor type as input and output parameters:

-- Cursor type input parameter
DECLARE
/* CURSOR cur_ttt IS
SELECT 1 a FROM dual ;*/

TYPE typ_cur is ref cursor;
Val_cur typ_cur;

PROCEDURE temp_sp1 (x_cur OUT typ_cur) IS
BEGIN
OPEN x_cur for select 1 a FROM dual union all select 2 FROM dual;
END;

PROCEDURE temp_sp2 (p_cur IN typ_cur) IS
I NUMBER;
BEGIN
LOOP
FETCH p_cur INTO I;
Exit when p_cur % NOTFOUND;
Dbms_output.put_line (I );
End loop;
CLOSE p_cur;
END;
BEGIN
Temp_sp1 (val_cur );
Temp_sp2 (val_cur );

OPEN val_cur for select 3 a FROM dual union all select 4 FROM dual;
Temp_sp2 (val_cur );
END;