varchar size

REGARDING                varchar size

Given the results of a query using the perl interface to postgres, how can I
find the maximum length of the data returned for the varchar fields in the
query?

Is there something in the "results" buffer or can I query the system catalogs
for this information?  If you need to query the system catalogs, what field
actually contains the maximum length of a varchar field?  In other words, how
can I find what the field was defined as in the create table statement (e.g.,
...attribute1  varchar(12)...) using the system catalogs?

TIA,
Andy