PHP获取机台mac

//获取电脑物理地址，区分机台
    public function getMacAddr()
    {
        $this->forWindows();
        $temp_array = array();
        foreach ($this->return_array as $value) {
            if (preg_match("/[0-9a-f][0-9a-f][:-]" . "[0-9a-f][0-9a-f][:-]" . "[0-9a-f][0-9a-f][:-]" . "[0-9a-f][0-9a-f][:-]" . "[0-9a-f][0-9a-f][:-]" . "[0-9a-f][0-9a-f]/i", $value, $temp_array)) {
                $this->mac_addr = $temp_array[0];
                break;
            }
        }
        unset($temp_array);
        return $this->mac_addr;
    }

    public function forWindows()
    {
        @exec("ipconfig /all", $this->return_array);
        if ($this->return_array)
            return $this->return_array;
        else {
            $ipconfig = $_SERVER["WINDIR"] . "\system32\ipconfig.exe";
            if (is_file($ipconfig))
                @exec($ipconfig . " /all", $this->return_array);
            else
                @exec($_SERVER["WINDIR"] . "\system\ipconfig.exe /all", $this->return_array);
            return $this->return_array;
        }
    }