How to know whether Wayland or X11 is being used

Question

I just installed the latest Kali Linux on my laptop which was based on Debian 7 (oldstable). I then dist-upgrad-ed the whole thing to Debian 8.

I've always wanted Wayland instead of X11, so I installed the necessary packages. Then created a minimal ~./config/weston.ini configuration. Now, from the Gnome login screen:

I can boot to Gnome on Wayland or LXDE (among others). The previous with very limited success and the latter (LXDE) almost perfectly, though the panel needs setting up (I have to look up freedesktop).

Anyways, in LXDE, the GUI is more responsive than it was on the oldstable and possibly as fast when it was running Windows 7. I was pleased.

But I want to know if this is because of all the library/module upgrades from Debian 7 to 8 or from using Wayland (if I really am using Wayland at all). I skimmed through htop and found a /usr/bin/Xorg running and no process named "wayland". So which one am I currently running?

Answer 1

Obtain the session ID to pass in by issuing:

loginctl

That will show you something like:

SESSION  UID USER          SEAT  TTY
     c2 1000 yourusername  seat0    

1 sessions listed.

In that example, c2 is the session ID.

Then:

loginctl show-session <SESSION_ID> -p Type

If you want all this on a single command:

loginctl show-session $(awk '/tty/ {print $1}' <(loginctl)) -p Type | awk -F= '{print $2}'

Use the one corresponding to your user name.

Refer to: https://fedoraproject.org/wiki/How_to_debug_Wayland_problems

So, for me it is:

$ loginctl show-session 2 -p Type                                                  
Type=wayland

Answer 2

How to know whether Wayland or X11 is being used?

on X11 systems:

$ echo $XDG_SESSION_TYPE
x11

on some wayland system:

$ echo $XDG_SESSION_TYPE
wayland

edit: This doesn't seem to work in some cases. See comments & use antismap's answer instead

Answer 3

This works on Fedora and Ubuntu 18.04.5 LTS:

loginctl show-session $(loginctl | grep $(whoami) | awk '{print $1}') -p Type

Answer 4

I like Ayush's answer the best, but thought I'd say that Andreas's answer can be done in one line:

loginctl show-session "$XDG_SESSION_ID" -p Type

You can additionally pass --value to drop the Type= prefix.

Answer 5

The simplest thing to do is to check whether WAYLAND_DISPLAY variable is set or not.

Answer 6

Tell which session type with POSIX-shell grammar and no sub-shell:

printf 'Session is: %s\n' "${DISPLAY:+X11}${WAYLAND_DISPLAY:+WAYLAND}"

Alternative handling all 4 states:

case $((0${DISPLAY:+1} | 0${WAYLAND_DISPLAY:+2})) in
1) session=X11 ;;
2) session=WAYLAND ;;
3) session='both X11 and WAYLAND' ;;
*) session='neither X11 nor WAYLAND' ;;
esac

printf 'Session is: %s\n' "$session"

Answer 7

Give the command

ps aux | grep gnome-shell

It will give the output

/usr/bin/gnome-shell --wayland --display-server

If Wayland is active.

Answer 8

If you're running Gnome, run the command r in the Alt+F2 menu. It will restart the environment (gnome-shell) in Xorg (without losing windows and processes) but in Wayland it will give the message "Restart is not available in Wayland".

Answer 9

The simple easy way to find out if you have Wayland or X11 is to open Settings, scroll down to About, and then scroll down to Windowing System, and it will tell you there.

In my own search for the answer to this question, after reading some of these "Answers," and finally finding out which I have through various Terminal commands, I found this much simpler way on my own. I'm brand new to Linux and I've been going through a lot of trouble shooting issues, and this kind of problem often comes up. It is extremely frustrating. Why does everyone offer such convoluted answers instead of the simpler more obvious solution?

Answer 10

You could run the xdpyinfo command. It gives information about your current X11 server (and display). It would fail if you don't have one (e.g. in a pure Wayland setting).

Answer 11

if you want a visual hint, I wrote a simple GNOME Shell extension that shows an icon that tells you whether you are running Wayland or Xorg

http://www.fepede.net/blog/2017/04/gnome_shell_extension_xorwayland/

Answer 12

No, I've noticed a pid called Wayland in htop, when I've switched to Wayland for giggles. Unless it's changed that's what one should see. Update: Here is a screengrab showing Wayland process.

Answer 13

Well you could also just check if applications are running in their wayland native form:

cd /usr/bin
ldd $application_name | grep wayland

Furthermore, to check which binaries have wayland support you could try:

cd /usr/bin
find . | xargs ldd | grep wayland -B 55

The above is not really very clean but it works. You can further pipe it to a file and then use vim to navigate.

cd /usr/bin
find . | xargs ldd | grep wayland -B 55 >> candidates
vim candidates
# Use vi movement

The -B flag stands for before and helps to print the binary name.

You could check this for more details. This answer adapted from this question.