about psql user

sorry, if its not a quiestion for the list, but i want know if is
posible config one user with readonly access to a DB in postgresql, i'm
seeking it in the manual and only found a entry in a Postgre95 ver 0.3
manual :-( nothing in the 7.4.2 documentation, i'm devel an app with php
and pgsql and some users only can make selects without inserts, deletes
or updates and this is the reason for the readonly user.

Thanks for your help.

Regards

Joe Nilson