General :: Trying To Test PHP Connectivity To Postgresql 8.3.9 Setup

I'm learning via baptism by fire method here, and need to test PHP connectivity to a local postgresql 8.3.9 setup. (CentOS 5.5 x86_64). I have got PHP and Postgres both working; I can pull up a test PHP page via web browser, and I can login to postgres via the command line. What I can't figure out is how to test PHP connectivity to the local DB.

I found this test script:
Code:
<?php
$conn = pg_connect ('dbname=template1');
?>

Which I've named, testdb.php - when I run ./testdb.php from the CLI though, I get:
Code:
./testdb.php: line 2: ?php: No such file or directory
./testdb.php: line 3: syntax error near unexpected token '"dbname=template1"'
./testdb.php: line 3: `$database=pg_connect ("dbname=template1");'

I've seen a LOT of pages describing the internal code of the PHP file, but as a newb to this, I don't know how to execute this test. I've ran chmod 755 against the file to verify permissions, but this didnt effect the results. I've also done a "chmod +x testdb.php"
Code:
PHP 5.1.6 (cli) (built: Mar 31 2010 02:39:17)

I realized I wasn't doing this:
Code:
php testdb.php
but when I do, I get this error message now:
"PHP Fatal error: Call to undefined function pg_connect() in /var/www/html/testdb.php on line 3"