SQL & PL/SQL

Hi all,

How could I do select for update in a dynamic cursor? I try to do:

declare
..type r_cursor is REF CURSOR;
..c_emp r_cursor;
begin
..open c_emp for select * from emp FOR UPDATE;
..loop
....fetch c_emp into er;
....exit when c_emp%notfound;

....--Data processing
....UPDATE EMP SET COLUMNX = 'XX' CURRENT OF c_emp;

..end loop;
..close c_emp;
end;

I read that we can't do UPDATE in a REF CURSOR, so How could I do a dynamic cursor for update?

Thanks!