Retrieval of OO objects.

Is it possible in postgres to retrieve objects with differing fields,
like in an object database? Like if I have

CREATE TABLE aaa ( a text );

CREATE TABLE bbb ( b text ) inherits (aaa);

CREATE TABLE ccc ( c text ) inherits (aaa);

SELECT * from aaa*;

Is it possible to get the fields a and c returned on objects of type bbb
and ccc? This is what an object database would do automatically.

I ask this question both in terms of the C interface as well as the psql
terminal program.