how can i check cron tab log

[eluser]Angel Lay[/eluser]
Hello

I want to create cronjob that i never try before.

I created cron.php. The content is below:

Code:

<?php
$url = 'http://test.com/controller/method';
file_get_contents($url);
?>

reference : http://ellislab.com/forums/viewthread/201824/#995592

The things i have done in crontab
/usr/bin/php -q /var/.../myroot/cron.php

But, it seems not working.Is there anything wrong?
how can i check log or something else that show the error?
I use Plesk Control Panel.

Thanks.