Because the Process Control Extensions' documentation is a bit rough, I decided to figure it out once, and then wrap my knowledge and the required code inside a PEAR class called: System_Daemon. And so now you can just:
require_once "System/Daemon.php"; // Include the Class
System_Daemon::setOption("appName", "mydaemon"); // Minimum configuration
System_Daemon::start(); // Spawn Deamon!
And that's all there is to it. The code after that, will run in your server's background. So next, if you create a while(true) loop around that code, the code will run indefinitely. Remember to build in a sleep(5) to ease up on system resources.
Features & Characteristics Here's a grab of System_Daemon's features:
Daemonize any PHP-CLI script
Driver based Operating System detection
Additional features for Debian / Ubuntu based systems like:
Automatically generate startup files (init.d)
Support for PEAR's Log package
Can run with PEAR (more elegance & functionality) or without PEAR (for standalone packages)
Default signal handlers, but optionally reroute signals to your own handlers.
Set options like max RAM usage