number of records returned by cursors

Hi,
does anyone know if there is a way (in plpgsql) to obtain the number of
records returned by a cursor without fetching them all?

Using "FOUND" and "GET DIAGNOSTICS row_count" variables doesn't help me:
the only way seems to be fetching all the records.

I try to explain it better:

CREATE OR REPLACE FUNCTION test_cur() RETURNS void AS
$$
DECLARE
c CURSOR FOR SELECT 'foo' UNION SELECT 'bar';
i integer;
t text;
BEGIN
OPEN c;
RAISE INFO 'FOUND: %', FOUND;
GET DIAGNOSTICS i = row_count;
RAISE INFO 'row_count: %', i;

FETCH c INTO t;
RAISE INFO '1 row (of 2) fetched: %', t;
RAISE INFO 'FOUND: %', FOUND;
GET DIAGNOSTICS i = row_count;
RAISE INFO 'row_count: %', i;

FETCH c INTO t;
RAISE INFO '2 row (of 2) fetched: %', t;
RAISE INFO 'FOUND: %', FOUND;
GET DIAGNOSTICS i = row_count;
RAISE INFO 'row_count: %', i;

CLOSE c;
END;
$$ LANGUAGE plpgsql;

SELECT test_cur();
INFO: FOUND: f
INFO: row_count: 0
INFO: 1 row (of 2) fetched: bar
INFO: FOUND: t
INFO: row_count: 0
INFO: 2 row (of 2) fetched: foo
INFO: FOUND: t
INFO: row_count: 0
test_cur
----------

(1 row)

Thank you.
Zac