• Launchpad Entry: mid-display-manager

  • Created: 2008-11-21

  • Contributors: Emmet Hikory

  • Packages affected:


The MID environment is currently launched by startx, which misses several components of session startup. Further, there is no means by which a user may create a guest session, or switch to a different username. Using a desktop manager would resolve many of these issues.

Release Note

Ubuntu MID now supports customisation of usernames, the setting of user passwords, and a better integration with granular system permissioning systems.


For Intrepid, the MID images launched the interface with a call to startx in /etc/event.d/session. This is fragile, does not integrate well with policykit or consolekit, currently expects hardcoded usernames, and should generally be replaced with something sensible.

Use Cases

  • Alice wishes to use a custom username for Ubuntu MID to better match her other systems.
  • Bob wants to set up password protection on his MID, so that if someone turns it on, they are not automatically granted access to his private data.
  • Chris starts a session in Ubuntu MID, and expects to have system authentication services available


  • It's easier integrate with policykit, consolekit, user-setup, oem-install, and other tools with a display manager than to extend the startx solution to perform these tasks.


After discussion, the decision was to keep the startx approach and fix the collateral bugs.


Use the target username instead of hardcoding "ubuntu"; bug #319393.

This means changing casper to generate a Xsession.d snippet which uses the proper username, or a /etc/default/ubuntu-mid-default-settings which is sourced to set an $USERNAME.

This also means changing user-setup to seed the target file (either Xsession.d or /etc/default) with the target username selected during install.

  • See my comments in the bug above; it would be better to just do it all in casper rather than changing user-setup. --ColinWatson

Extend ck-launch-session to provision X $DISPLAY information instead of stripping XDG_SESSION_COOKIE; bug #319396.

Test plan

Verify that automounting of USB sticks (which is granted by ConsoleKit) works from a live and an installed system. Check with an installed system using the default ubuntu username, and with another username.


Specs/MidDisplayManager (last edited 2009-03-17 14:20:55 by 82-69-40-219)