> There is no threading support whatsoever.
>> That's a good thing. It forces you to use async HTTP programming or something like beanstalk, both of which are better than the complexity of threading.
While there isn't multi-threading in PHP, you can in fact multi-process which provides similar functionality.
While there aren't many cases where you should run PHP as a daemon or cron job, there are _some_. Like, for example, you've got dozens of models and helpers written in PHP and you want to use them in queue workers or aggregation jobs.
I've run into these a few times and acquired a bit of mastery of PHP's PCNTL, POSIX and Semaphore/SHM/IPC extensions.
I don't do much PHP work anymore, but I do maintain an OSS library for other people in that situation: PHP Simple Daemon -- https://github.com/shaneharter/PHP-Daemon
While there isn't multi-threading in PHP, you can in fact multi-process which provides similar functionality.
http://php.net/manual/en/function.pcntl-fork.php