PHP pg_connect - Mailing list pgsql-general

When this fails, I get a useful error print:

$dbconn = pg_connect($connection_str);

Ouput:

Warning: pg_connect() [function.pg-connect]: Unable to connect to
PostgreSQL server: FATAL: password authentication failed for user
"postgres1" in ...

How do I capture this error and handle the printing myself?  I want to
be able to know why it failed... ie password in this case.

Thanks,
Vince.