I was wondering who actually calls /usr/sbin/lightdm-session during the startup proccess. It seems be hard-coded in LightDM somewhere to execute this script when a user log in and a new session is started?
The only place I found where it is called is also commented out so it is no longer called on line 11:
$ cat /usr/lib/lightdm/config-error-dialog.sh # Copyright (C) 2014 Canonical Ltd # Author: Gunnar Hjalmarsson <firstname.lastname@example.org> # # This program is free software: you can redistribute it and/or modify it under # the terms of the GNU General Public License as published by the Free Software # Foundation, version 3 of the License. # # See http://www.gnu.org/copyleft/gpl.html the full text of the license. # This file may be sourced by the function source_with_error_check() in # /usr/sbin/lightdm-session export TEXTDOMAIN=lightdm . /usr/bin/gettext.sh PARA1=$(eval_gettext 'Error found when loading $CONFIG_FILE:') PARA2=$(gettext 'As a result the session will not be configured correctly. You should fix the problem as soon as feasible.') TEXT="$PARA1\n\n$(fold -s $ERR)\n\n$PARA2" if [ -x /usr/bin/kdialog ]; then TEXT_FILE=$(mktemp --tmpdir config-err-kdialog-XXXXXX) echo -n "$TEXT" > "$TEXT_FILE" kdialog --textbox "$TEXT_FILE" 500 300 rm -f "$TEXT_FILE" elif [ -x /usr/bin/zenity ]; then zenity --warning --no-wrap --text="$TEXT" fi