设置有线mac地址

ifconfig eth0 hw ether 021234567000

读取mac地址

    public static String getEthMacAddressBySysFs() {
        try (BufferedReader reader = new BufferedReader(new FileReader("/sys/class/net/eth0/address"))) {
            return reader.readLine().trim(); // 如 "00:11:22:33:44:55"
        } catch (Exception e) {
            return "00:00:00:00:00:00";
        }
    }

设置屏幕亮度

        val ps = Runtime.getRuntime().exec("su") //1、执行su切换到root权限
        val dos = DataOutputStream(ps.outputStream)
        dos.writeBytes("echo 200 > /sys/class/backlight/backlight/brightness" + "\n") // 2、向进程内写入shell指令，cmd为要执行的shell命令字符串
        dos.flush()

关闭后台进程

dos.writeBytes("am force-stop \"org.videolan.vlc\"" + "\n")