X11 Window System


Looking around on Ubuntu

/etc/X11 is a good place to start

Xsession is invoked by the display manager.

See ‘man 5 Xsession’

Xsession redirects stdout & stderr to $HOME/.xsession-errors almost first thing

Xsession.d/* has a bunch of scripts that are sourced in order by Xsession:

  • 20x11-common_process-args: sets STARTUP if arg passed to Xsession

  • 40x11-common_xsessionrc: will source $HOME/.xsessionrc if it is readable

  • 50x11-common_determine-startup: will set STARTUP to ~/.xsession or ~/.Xsession but ONLY if the display manager has not already set a startup command by passing it to Xsession - or so the comments say…

Also look at /etc/kde4/kdm:

  • kdmrc: LOTS of useful config stuff - read the comments

Which directories kdm looks in for different desktop sessions - It might just use the first of these where it finds anything??????

  • /usr/share/xsessions

  • /var/lib/menu-xdg/xsessions (no such dir)

  • /etc/kde4/kdm/sessions (empty)

  • /usr/share/kde4/apps/kdm/sessions (a zillion files, I suspect it doesn’t look here since others come first)