EXCEPTION in pl/pgsql

Hi All

What is the syntax if I want to use the exception clause in a pl/pgsql
function, but am not looking for a particular error. Kind of like a "any
error" type thing.

some thing like:

CREATE OR REPLACE FUNCTION func1(p_Param1 int4)
RETURNS int4
AS
$$

DECLARE
v_Var1 int4;

BEGIN
[Statements]
RETURN 1;

EXCEPTION
WHEN <any_error> THEN
ROLLBACK;
RETURN -1;
END;
$$ LANGUAGE 'plpgsql' volatile;

What should I replace <any_error> with?

Thanks