PHP implementation code to obtain MAC address

/**
* Obtain the physical (MAC) address of the machine's network card
* Currently supports WIN/LINUX system
* Editor: bbs.it-home.org
**/
class MacAddInfo {
    var $return_array = array (); // 返回带有MAC地址的字串数组
    var $mac_addr;

    function MacAddInfo($os_type) {
        switch (strtolower ( $os_type )) {
            case "linux" :
                $this->forLinux ();
                break;
            case "solaris" :
                break;
            case "unix" :
                break;
            case "aix" :
                break;
            default :
                $this->forWindows ();
                break;
        }
        $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;
    }

    function forWindows() {
        @exec ( "ipconfig /all", $this->return_array );
        if ($this->return_array)
            return $this->return_array;
        else {
            $ipconfig = $_SERVER ["WINDIR"] . "system32ipconfig.exe";
            if (is_file ( $ipconfig ))
                @exec ( $ipconfig . " /all", $this->return_array );
            else
                @exec ( $_SERVER ["WINDIR"] . "systemipconfig.exe /all", $this->return_array );
            return $this->return_array;
        }
    }

    function forLinux() {
        @exec ( "ifconfig -a", $this->return_array );
        return $this->return_array;
    }
}
//调用示例
//$mac = new MacAddInfo(PHP_OS);
//echo $mac->mac_addr;
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