Using Android Emulator's Root Shell via Command Line

Question

I want to get a root shell since my adbd crashes. But the -shell option does not work. Meanwhile, I found out, that you can get a shell by using -show-kernel. But I would like to communicate with the root shell by TCP. There's also an open issue at google: https://code.google.com/p/android/issues/detail?id=202760

When starting an Android emulator (SDK 24.4.1) on Linux by command line, you should be able to get a root shell by using the -shell command-line option. At least that's what the manual says

Create a root shell console on the current terminal. You can use this command even if the adb daemon in the emulated system is broken. Pressing Ctrl-C from the shell stops the emulator, instead of the shell

But when starting the emulator like

emulator -netdelay none -netspeed full -avd nougat-x86_64 -gpu off -no-window -shell

I do see the shell output of the Android emulator booting, but I cannot send any commands to it, i.e. ls.

Also, opening a TCP port for the shell and communicating via telnet shows the same behavior.

emulator -netdelay none -netspeed full -avd nougat-x86_64 -gpu off -no-window -shell-serial tcp::4444,server,nowait
telnet localhost 4444

There's not much information about this topic on the internet, but perhaps someone already dealt with this topic.

Answer 1

From Android source line 698, seems the -shell option is as same as -logcat option, thus I think the documentation is not described well and of course the -shell option won't bring you an interactive root shell from the virtual serial. Maybe I'm wrong, I only tested this on macOS.

With a further test, as same as this guy's post, the -show-kernel will actually get you the kernel log and an interactive rootable console.