Atomic script locker - ensure that ONLY a single instance of your script (cronjob) runs at a time.
Solo will only work on scripts you run from the command line.
Your cronjob will look like.
require 'Solo.php';
//setup
$lock = new Solo('my-lock-name');
//check if already running
if (!$lock->isLocked()) die('Already running.');
// do the work
echo "Working!";
sleep(15);
//no clean-up requiredCopyright (c) 2014 Dan Hollenbeck
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