Introduction to Lightdm

The lightdm package contains a lightweight display manager based upon GTK.

This package is known to build and work properly using an LFS-8.4 platform.

Lightdm Package Information



The greeter is a program to present a graphical login screen. There are several alternative greeters, but the gtk+ package is the reference implementation. For a list of other greeters, see

Lightdm-gtk-greeter Package Information

Lightdm Dependencies


GTK+-3.24.7, libgcrypt-1.8.4, Linux-PAM-1.3.0, and PCRE-8.43



at-spi2-core-2.32.0, Exo-0.12.4, GTK-Doc-1.29, itstool-2.0.5, Qt-5.12.2, libido, and libindicator

User Notes:

Installation of Lightdm

First, create a dedicated user and group to take control of the lightdm daemon after it is started. Issue the following commands as the root user:

groupadd -g 65 lightdm       &&
useradd  -c "Lightdm Daemon" \
         -d /var/lib/lightdm \
         -u 65 -g lightdm    \
         -s /bin/false lightdm

Install lightdm by running the following commands:

./configure                          \
       --prefix=/usr                 \
       --libexecdir=/usr/lib/lightdm \
       --localstatedir=/var          \
       --sbindir=/usr/bin            \
       --sysconfdir=/etc             \
       --disable-static              \
       --disable-tests               \
       --with-greeter-user=lightdm   \
       --with-greeter-session=lightdm-gtk-greeter \
       --docdir=/usr/share/doc/lightdm-1.28.0 &&

This package does not come with a test suite.

Now, as the root user:

make install                                                  &&
cp tests/src/lightdm-session /usr/bin                         &&
sed -i '1 s/sh/bash --login/' /usr/bin/lightdm-session        &&
rm -rf /etc/init                                              &&
install -v -dm755 -o lightdm -g lightdm /var/lib/lightdm      &&
install -v -dm755 -o lightdm -g lightdm /var/lib/lightdm-data &&
install -v -dm755 -o lightdm -g lightdm /var/cache/lightdm    &&
install -v -dm770 -o lightdm -g lightdm /var/log/lightdm

Now build the greeter:

tar -xf ../lightdm-gtk-greeter-2.0.5.tar.gz &&
cd lightdm-gtk-greeter-2.0.5 &&

./configure                      \
   --prefix=/usr                 \
   --libexecdir=/usr/lib/lightdm \
   --sbindir=/usr/bin            \
   --sysconfdir=/etc             \
   --with-libxklavier            \
   --enable-kill-on-sigterm      \
   --disable-libido              \
   --disable-libindicator        \
   --disable-static              \
   --docdir=/usr/share/doc/lightdm-gtk-greeter-2.0.5 &&


Now, as the root user:

make install

Command Explanations

sed ... /usr/bin/lightdm-session: This command ensures that the initial login via the greeter sources /etc/profile and ~/.bash_profile. Without this, commands that depend on different environment variables may not work as expected.

Configuring lightdm

Config Files


Boot Script

Install the /etc/rc.d/init.d/lightdm init script from the blfs-bootscripts-20190313

make install-lightdm

Starting lightdm

If the lightdm bootscript has been installed, start lightdm by running, as the root user:

/etc/rc.d/init.d/lightdm start

By convention, X should be executed at runlevel 5, consequently, the same is true for lightdm. However, LFS default runlevel is 3. Changing to runlevel 5, from a console terminal, as root user, starts the lightdm bootscript, bringing up the greeter screen:

init 5

In order to permanently set the default to 5, starting the lightdm greeter screen automatically, modify /etc/inittab. As the root user:

cp -v /etc/inittab{,-orig} &&
sed -i '/initdefault/ s/3/5/' /etc/inittab

Available Sessions

The greeter offers a list of available sessions, depending on the Window Managers and Desktop Environments installed. The list includes sessions which have a corresponding .desktop file installed under /usr/share/xsessions. Most of the Window Managers and Desktop Environments automatically provide those files, but if necessary, you may include a custom one.


Installed Programs: dm-tool, lightdm, and lightdm-gtk-greeter
Installed Libraries:
Installed Directories: /etc/lightdm, /etc/apparmor.d, /usr/lib/lightdm, /usr/include/lightdm-gobject-1, /usr/share/help/C/lightdm /usr/share/gtk-doc/html/lightdm-gobject-1, /usr/share/doc/lightdm-gtk-greeter-2.0.5, /var/lib/lightdm, /var/lib/lightdm-data, /var/cache/lightdm, and /var/log/lightdm

Short Descriptions


is a display and login manager.


is an auxiliary process that displays the greeter, a graphical user interface that performs user authentication and initiates the selected window manager or display environment.

Last updated on 2019-02-20 17:33:51 -0600