curl asynchrone pool

<?php
// Create a curl handle to a non-existing location
$ch = curl_init('http://www.example.com/doesntexist');
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);

// Create a DOM object
$dom = new DOMDocument;

// Augment the DOM object with the addCallback function
$dom->addCallback = function($ch, $data) use ($dom) {
    @$dom->loadHTML($data);
};

// Set your options and execute
curl_setopt_array($ch, array(
    CURLOPT_URL => "http://www.example.com/",
    CURLOPT_FOLLOWLOCATION => true,
    CURLOPT_MAXREDIRS => 2,
    CURLOPT_COOKIEFILE => "",
    CURLOPT_COOKIEJAR => "",
    CURLOPT_USERAGENT => "Mozilla/5.0 (X11; U; Linux x86_64; en-US;