Hprose\Swoole\Socket\FullDuplexTransporter::fetch PHP Method

    public function fetch()
    {
        while (!empty($this->pool)) {
            $conn = array_pop($this->pool);
            if ($conn->isConnected()) {
                if ($conn->count === 0) {
                    swoole_timer_clear($conn->timer);
                    $conn->timer = null;
                    $conn->wakeup();
                }
                return $conn;
            }
        }
        return null;
    }