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Is it possible to unlock the 13.04 Gnome shell login screen from a command line? A user is logged in to Gnome shell, I can log in to a console as this user. I also have root access.

This is for accessing an active X11 display through VNC, without having to enter the password.

Executing

gnome-screensaver-command -d

as suggested in a blog post didn't help.

login screen

Braiam
  • 69,112
krlmlr
  • 3,447

5 Answers5

79

I'm assuming you have a recent linux system with systemd (e.g. Ubuntu 16.04 or newer).

If you need to unlock your own session, just run loginctl unlock-session (no root required because it's your own session). If you have multiple sessions and want to select just one, run loginctl list-sessions to identify session and then run e.g. loginctl unlock-session c187.

If you need to unlock all sessions, just run sudo loginctl unlock-sessions (note plural form). Note that this will immediately unlock ALL sessions no matter which user is running the screen saver.

If you need more information to identify the correct session, you can try something like this:

loginctl list-sessions --no-legend | while read id rest; do echo; loginctl show-session $id; done
Mikko Rantalainen
  • 3,785
24

The problem with executing commands like gnome-screensaver-command from an SSH session is usually that they don't automatically connect to the appropriate session bus for the active desktop session - usually, setting the DISPLAY variable will fix that, for example these work for me (logged in via SSH as the same user who owns the locked X session, which is on DISPLAY :0):

$ DISPLAY=:0 gnome-screensaver-command -d

to unlock, and

$ DISPLAY=:0 gnome-screensaver-command -l

to lock.

Alternatively, you can toggle the active state using dbus-send - for example

$ export DISPLAY=:0
$ dbus-send --session \
          --dest=org.gnome.ScreenSaver \
          --type=method_call \
          --print-reply \
          --reply-timeout=20000 \
          /org/gnome/ScreenSaver \
          org.gnome.ScreenSaver.SetActive \
          boolean:false

Source: https://people.gnome.org/~mccann/gnome-screensaver/docs/gnome-screensaver.html#gs-examples

steeldriver
  • 142,475
8

The following worked for me:

sudo killall gnome-screensaver

Especially helpful when you're logged in via SSH with another user.

rosch
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4

I had a problem with gnome 3's screen lock (screensaver) being stuck at a blank screen. I managed to work around it by replacing the gnome-shell window manager.

Ctrl+Alt+F1 and log in on a virtual console, then:

pkill -QUIT gnome-shell
DISPLAY=:0.0 gnome-shell -r &

(& Backgrounds the new gnome-shell so you can log out of the virtual console and keep it running. Alternatively use Ctrl+Z to suspend the gnome-shell process, and bg to background it.)

It might not be elegant, but it finally allowed me to get back to my desktop apps without having gnome force me to logout.

T Percival
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  • 1
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1

I had a similar problem where the unlock screen wouldn't accept keyboard input sometimes. The way I finally solved it was to kill the several gnome-screensaver processes that were running, as well as one gnome-screensaver-dialog process. I'm guessing that whatever process was spawning 2 gnome-screensaver sessions was messing up my unlock screen. I'm actually supposed to be using xscreensaver instead, so maybe that messed with it.

Anyways, Ctrl+Alt+F1, look for screensaver processes running ps -aux | grep screen and kill them all. The gnome and xscreensaver commands listed in the other answers didn't work for me.

Scott
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