curl asynchrone pool

$rand = rand(1, 10);

$curl = new \Curl\Curl();
$curl->on('success', function ($instance) {
    echo 'call to "' . $instance->url . '" was successful.' . "\n";
});
$curl->on('error', function ($instance) {
    echo 'call to "' . $instance->url . '" was unsuccessful.' . "\n";
    echo 'error code: ' . $instance->errorCode . "\n";
    echo 'error message: ' . $instance->errorMessage . "\n";
});
$curl->on('complete', function ($instance) {
    echo 'call to "' . $instance->url . '" completed.' . "\n";
});
for ($i = 1; $i <= $rand; $i++) {
    $curl->get('http://www.example.com/');
}
$curl->start();