adb on linux

question:

1. adb devices

    1234567890ABCDEF device

    1234567890ABCDEF device

2. adb -s 1234567890ABCDEF shell

   more than one device

how can i reach one of these two devices when their serial no are the same with each other?

First of all, i consider of access device by index, only to find that the dab tool did not provide us such usage;

Secondly, how about rewrite a different serial no to one of my mobile phone?

Having searched so many papers about this topic , one message open to my eyes,written like this:

1. adb shell
2.cd /sys/class/android_usb/android0/
3.echo -n 你想要的字符串 > iSerial
4. cat iSerial,确认更改成功
5.重新插拔usb。
需要root权限

Does this method works?

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