SLiM

From Gentoo Wiki
Jump to:navigation Jump to:search
Note
The original SLiM project, from which versions up to 1.3.6 were obtained, was abandoned in 2013. Subsequent versions are from an actively maintained fork by a different author.

SLiM (Simple Login Manager) is a desktop-independent graphical display manager. Being fast and having only a few dependencies, it is a popular choice among users of lightweight window managers such as Openbox.

Installation

USE flags

USE flags for x11-misc/slim Simple Login Manager resurrected

branding Enable Gentoo specific branding
pam Add support for PAM (Pluggable Authentication Modules) - DANGEROUS to arbitrarily flip

Emerge

Install x11-misc/slim:

root #emerge --ask x11-misc/slim
Note
Enable the pam USE flag for x11-misc/slim if the slimlock command is needed for locking the screen.

Configuration

Files

Most global configuration is done in the /etc/slim.conf file. However, this references several helper scripts which may contain further configuration.

Service

OpenRC

With display-manager

Set SLiM as the default display manager:

FILE /etc/conf.d/display-manager
DISPLAYMANAGER="slim"

To start SLiM on boot, add display-manager to the default runlevel:

root #rc-update add display-manager default

To start SLiM now:

root #rc-service display-manager start
With the deprecated xdm init script

Set SLiM as the default display manager:

FILE /etc/conf.d/xdm
DISPLAYMANAGER="slim"

To start SLiM on boot, add xdm to the default runlevel:

root #rc-update add xdm default

To start SLiM now:

root #/etc/init.d/xdm start

systemd

To start SLiM on boot:

root #systemctl enable slim

To start SLiM now:

root #systemctl start slim

Session selection

SLiM starts the user's preferred desktop session through a helper. There are several options for how this is done.

Upstream-style configuration

This method provides full flexibility per user, at the cost of requiring all users to have the helper script in their home directory.

Make the config section look like this:

FILE /etc/slim.confModifying slim.conf
# login_cmd           exec /bin/sh - ~/.xinitrc %session
login_cmd           exec /bin/bash -login ~/.xinitrc %session
# login_cmd           exec /bin/bash -login /usr/share/slim/Xsession %session

Each user must setup a window manager of choice in their ~/.xinitrc. If the user chooses a different session from the login page, that will be passed as an argument to the script. If $1 is empty it should run the user's default session.

Default configuration (Gentoo-style)

Note
In the following paragraphs Awesome window manager is used as an example window manager.

By default, SLiM is configured to make all sessions in /etc/X11/Sessions/ accessible — they can be cycled through by pressing the F1 key. This behavior is acquired by setting the options below:

FILE /etc/slim.confEditing session behavior
login_cmd            exec /bin/bash -login /usr/share/slim/Xsession %session
...
sessiondir           /etc/X11/Sessions

If no changes are made to /etc/X11/Sessions/ then users will need to press F1 while logging-in to select the desired session.

In following sections several methods of setting one session as the default are described.

Warning
Some window managers do not provide session file and therefore cannot be seen in /etc/X11/Sessions/ by SLiM. In that case use the second method of setting a default session for one user (using a custom ~/.xsession file), because neither global nor "per-user bundled session files" methods will work. You may also want to file a bug, asking a developer to add a session file to the ebuild.
Setting a global default session

Set a default session for all users of the computer by modifying the XSESSION variable. To do this, create and edit file /etc/env.d/90xsession file. The example below sets the Awesome window manager as the default session.

FILE /etc/env.d/90xsession
XSESSION="awesome"

After saving the file run env-update:

root #env-update
Setting a default session for one user

Besides (or instead of) setting global default sessions, it is possible to let each user choose a default session.

There are three approaches to accomplishing the task:

  • Use the SLiM session script (/usr/share/slim/Xsession) to trigger session script from /etc/X11/Sessions/
  • Use the SLiM session script to trigger user-created session script
  • Force users to set everything by themselves

The first and second possibilities are generally preferred. However, if for any reason you do not want to set any defaults, you may choose the third approach.

Per-user default session using bundled session files

The simplest way to set a default session for one user is to make a symbolic link from the session file to ~/.xsession

user $ln -s /etc/X11/Sessions/awesome ~/.xsession

An alternative is to put session command in the ~/.xsession file:

FILE ~/.xsession
/etc/X11/Sessions/awesome

You will only need to make sure the file is executable:

user $chmod u+x ~/.xsession
Per-user default session using the customized ~/.xsession file

Sometimes you need to customize the launcher script, e.g. to run other programs before starting the window manager or to start a window manager with a customized command. The method above does not allow such modifications, but it can be achieved by using default session script (instead of the one provided by window manager) and launching WM through the ~/.xsession file.

To run your sessions this way, make sure you have no global default session set (or set it to XSESSION="custom" in /etc/env.d/90xsession like described above). Then edit the ~/.xsession file located in the user's home directory, putting the window manager launcher at the end.

The file may look like this:

FILE ~/.xsession
#!/bin/sh

# Run urxvt daemon
urxvtd -q -o -f
# Set xserver parameters
xset s 0
xset dpms 0 0 1800
# Launch awesome
exec /usr/bin/awesome
Tip
It might be helpful to look at the window manager session files in /etc/X11/Sessions/ to find how things are done.
Important
By default SLiM evaluates /usr/share/slim/Xsession first, then /etc/X11/Sessions/Xsession, and ~/.xsession is called last, so there is no need to duplicate entries from that two previous files.

Finally, remember to make sure the file is executable:

user $chmod u+x ~/.xsession
Per-user default session without using any default session files

If you do not like any defaults from /usr/share/slim/Xsession and /etc/X11/Sessions/Xsession, you can let your users set everything by themselves. It is generally not a good idea, but sometimes you may need it.

Warning
You must be sure that every user will know what they are expected to do and that they will have enough knowledge to create ~/.xinitrc by themselves. For example, when configuring SLiM in this way, neither .Xresources nor .Xkbmap files are read by default and no errorfiles are created.

Start by editing /etc/slim.conf in the following way:

FILE /etc/slim.conf
#login_cmd            exec /bin/bash -login /usr/share/slim/Xsession %session
login_cmd           exec /bin/bash -login ~/.xinitrc %session
...
#sessiondir           /etc/X11/Sessions
sessions            awesome,i3

In the sessions line you may put the names of window managers you are planning to use.

Then create and edit ~/.xinitrc file, which may look as below:

FILE ~/.xinitrc
#!/bin/sh
#
# Custom xinitrc file for Gentoo

DEFAULT_SESSION="awesome"

# Redirect errors to a file in user's home directory if we can
for errfile in "$HOME/.wm-errors" "${TMPDIR-/tmp}/wm-$USER" "/tmp/wm-$USER"
do
    if ( cp /dev/null "$errfile" 2> /dev/null )
    then
        chmod 600 "$errfile"
        exec > "$errfile" 2>&1
        break
    fi
done

# Define Xresources
userresources=$HOME/.Xresources

# Merge what is available
if [ -f "$userresources" ]; then
    xrdb -merge "$userresources"
fi

# Run urxvt daemon
urxvtd -q -o -f
# Set xserver parameters
xset s 0
xset dpms 0 0 1800

# Start WM
case $1 in 
awesome|i3)
        exec $1
        ;;
*)
        exec $DEFAULT_SESSION
        ;;
esac

Finally make sure the file is executable:

user $chmod u+x ~/.xinitrc

More tweaks

Theme selection

Note
You can install the package x11-themes/slim-themes for having various nice-looking themes you can choose from.

Theme selection is done by changing the following line:

FILE /etc/slim.conf
current_theme    slim-gentoo-simple

You can easily find what themes are available on your system:

user $ls /usr/share/slim/themes/

You can preview a theme by running the following command while Xorg is running:

user $slim -p /usr/share/slim/themes/<theme name>

NumLock state on login

The NumLock key can be turned on or off by default:

FILE /etc/slim.conf
numlock    on

Autologin

Change <USER> in the example below to an appropriate user name:

FILE /etc/slim.conf
default_user        <USER>
auto_login          yes

Unlock keyrings

The following section will describe how to make SLiM automatically unlock different keychains automatically when you log in.

GNOME Keyring

First make sure you have gnome-base/gnome-keyring (include app-crypt/seahorse if you want a GUI). To configure SLiM to unlock your GNOME Keyring automatically you have to edit its PAM configuration file. To do so open /etc/pam.d/slim and modify it to look similar to the text below. Lines ending with comment #keyring should be added.

FILE /etc/pam.d/slim
auth	include		system-local-login
auth  optional	pam_gnome_keyring.so #keyring
account	include		system-local-login
session	include		system-local-login
session optional	pam_gnome_keyring.so auto_start #keyring

Once this change has been made your keyring should be automatically unlocked next time you log in.

Troubleshooting

Failed to connect to socket /var/run/dbus/system_bus_socket

This error is caused when D-Bus hasn't been started. It is possible that it wasn't added to the default run level. To fix this type the following:

root #rc-update add dbus default

This will ensure that D-Bus is running when you boot up your computer. It may be that this has already been added by other window manager, but I had to do this when using awesome WM.

SLiM starts but leaves a blank screen after login

This error is caused when SLiM is built with the elogind USE flag, and required alongside

root #rc-update add xdm default

the use of

root #rc-update add elogind default

On fresh installs, slim starts but fails to load any sessions

In this error, slim will start and be responsive (you can type the username for example) but after the login no sessions will be loaded and you will get a blank screen. Pressing F1 to change the session will result in nothing. This can occur when dbus is not being loaded when the system starts. To add dbus to the default runlevel, use:

root #rc-update add dbus default

See also