Android shell setup hints ​

TRAMP uses the adb method to access Android devices. Android devices provide a restricted shell access through an USB connection. The local host must have the adb program installed. Usually, it is sufficient to open the file /adb::/. Then you can navigate in the file system via dired.

Alternatively, applications such as Termux or SSHDroid that run sshd process on the Android device can accept any ssh-based methods provided these settings are adjusted:

  • sh must be specified for remote shell since Android devices do not provide /bin/sh. sh will then invoke whatever shell is installed on the device with this setting:

    emacs-lisp
    (add-to-list 'tramp-connection-properties
             (list (regexp-quote "192.168.0.26") "remote-shell" "sh"))

    where ‘192.168.0.26’ is the Android device’s IP address. (see Setting own connection related information).

  • On the Android device the directory names are prefixed with an application specific prefix, which is /data/data/com.termux/files/usr/bin instead of /usr/bin in the Termux case. You must adapt the file names in tramp-remote-path, for example via connection-local settings:

    emacs-lisp
    (connection-local-set-profile-variables
 'tramp-connection-local-termux-profile
 `((tramp-remote-path
    . ,(mapcar
	(lambda (x)
	  (if (stringp x) (concat "/data/data/com.termux/files" x) x))
	(copy-tree tramp-remote-path)))))

(connection-local-set-profiles
 '(:application tramp :machine "192.168.0.26")
 'tramp-connection-local-termux-profile)

  • When the Android device is not ‘rooted’, specify a writable directory for temporary files:

    emacs-lisp
    (add-to-list 'tramp-connection-properties
             (list (regexp-quote "192.168.0.26")
		   "tmpdir" "/data/data/com.termux/files/home/tmp"))

  • Open a remote connection with the command C-x C-f /ssh:192.168.0.26#2222: RET, where sshd is listening on port ‘2222’.

    To add a corresponding entry to the ~/.ssh/config file (recommended), use this:

    Host android
     HostName 192.168.0.26
     User root
     Port 2222

    To use the host name ‘android’ instead of the IP address shown in the previous example, fix the connection properties as follows:

    emacs-lisp
    (add-to-list 'tramp-connection-properties
             (list (regexp-quote "android") "remote-shell" "sh"))
(add-to-list 'tramp-connection-properties
             (list (regexp-quote "android")
		   "tmpdir" "/data/data/com.termux/files/home/tmp"))
(connection-local-set-profiles
 '(:application tramp :machine "android")
 'tramp-connection-local-termux-profile)

    Open a remote connection with the more concise command C-x C-f /ssh:android: RET.