Global socket i php class

<?php
class AsyncOperation extends Thread {
    public function __construct($arg) {
		global $permit, $config, $vars, $global;
                $this->arg = $arg;
		$this->config = $config;
		$this->vars = $vars;
		$this->socket = $socket;
    }

    public function run() {
     
    }
}

$socket = fsockopen("0.0.0.0", 10000);

foreach(range("A","D") as $i){
 $stack[] = AsyncOperation($i);
}

foreach($stack as $i){
 $i->start();
}