How would test cron with Magento?

Question

First I need to understand how Magento cron works.

I know how cron works on linux, using crontab -e.
I know I need to set up Magento\'s cron.php to run

Answer 1

adding these to the bottom of cron.php will make it write out cron.php.log on execution with the datetime

try {
    Mage::getConfig()->init()->loadEventObservers('crontab');
    Mage::app()->addEventArea('crontab');
    Mage::dispatchEvent('default');

$log = fopen(__FILE__.'.log', 'a');
fwrite($log, date("Y-m-d H:i:s").PHP_EOL);
fclose($log);
} catch (Exception $e) {
    Mage::printException($e);
}