(PHP 4 )
is_resource() returns TRUE if the variable given by the var parameter is a resource, otherwise it returns FALSE.
Example 1. using is_resource()
<?php$db_link = @mysql_connect('localhost', 'mysql_user', 'mysql_pass');if (!is_resource($db_link)) { die('Can\'t connect : ' . mysql_error());}?>
See the documentation on the resource-type for more information.