Arch Linux

Description:
I build my system with x.org and LXDE in April this year,using systemd for bootstrap,and using slim to login to desktop without passwd.In August 1st the lxsession was upgrade from lxsession-0.4.6.1-3-x86_64 to lxsession-0.4.9.2-2-x86_64,and then my system can not shutdown by the desktop menu.When I downgrade the lxsession back to 0.4.6.1,it continue work.

Additional info:
$ cat /etc/slim.conf
# Path, X server and arguments (if needed)
# Note: -xauth $authfile is automatically appended
default_path /bin:/usr/bin:/usr/local/bin
default_xserver /usr/bin/X
xserver_arguments -nolisten tcp vt07

# Commands for halt, login, etc.
halt_cmd /sbin/shutdown -h now
reboot_cmd /sbin/shutdown -r now
console_cmd /usr/bin/xterm -C -fg white -bg black +sb -T "Console login" -e /bin/sh -c "/bin/cat /etc/issue; exec /bin/login"
#suspend_cmd /usr/sbin/suspend

# Full path to the xauth binary
xauth_path /usr/bin/xauth

# Xauth file for server
authfile /var/run/slim.auth


# Activate numlock when slim starts. Valid values: on|off
# numlock on

# Hide the mouse cursor (note: does not work with some WMs).
# Valid values: true|false
# hidecursor false

# This command is executed after a succesful login.
# you can place the %session and %theme variables
# to handle launching of specific commands in .xinitrc
# depending of chosen session and slim theme
#
# NOTE: if your system does not have bash you need
# to adjust the command according to your preferred shell,
# i.e. for freebsd use:
# login_cmd exec /bin/sh - ~/.xinitrc %session
login_cmd exec /bin/bash -login ~/.xinitrc %session

# Commands executed when starting and exiting a session.
# They can be used for registering a X11 session with
# sessreg. You can use the %user variable
#
# sessionstart_cmd some command
# sessionstop_cmd some command

# Start in daemon mode. Valid values: yes | no
# Note that this can be overriden by the command line
# options "-d" and "-nodaemon"
# daemon yes

# Available sessions (first one is the default).
# The current chosen session name is replaced in the login_cmd
# above, so your login command can handle different sessions.
# see the xinitrc.sample file shipped with slim sources
sessions xfce4,icewm-session,wmaker,blackbox

# Executed when pressing F11 (requires imagemagick)
screenshot_cmd import -window root /slim.png

# welcome message. Available variables: %host, %domain
welcome_msg Welcome to %host

# Session message. Prepended to the session name when pressing F1
# session_msg Session:

# shutdown / reboot messages
shutdown_msg The system is halting...
reboot_msg The system is rebooting...

# default user, leave blank or remove this line
# for avoid pre-loading the username.
default_user yssd

# Focus the password field on start when default_user is set
# Set to "yes" to enable this feature
#focus_password no

# Automatically login the default user (without entering
# the password. Set to "yes" to enable this feature
auto_login yes


# current theme, use comma separated list to specify a set to
# randomly choose from
current_theme default

# Lock file
lockfile /var/lock/slim.lock

# Log file
logfile /var/log/slim.log

[yssd@YS ~]$ sudo vim /etc/slim.conf
[sudo] password for yssd:
[yssd@YS ~]$ ls /var/
abs/ db/ games/ local/ log/ opt/ spool/
cache/ empty/ lib/ lock/ mail/ run/ tmp/
[yssd@YS ~]$ ls /var/cache/
fontconfig/ ldconfig/ man/ pacman/
[yssd@YS ~]$ ls /var/cache/pacman/pkg/lxsess*
/var/cache/pacman/pkg/lxsession-0.4.6.1-3-x86_64.pkg.tar.xz
/var/cache/pacman/pkg/lxsession-0.4.9.2-1-x86_64.pkg.tar.xz
/var/cache/pacman/pkg/lxsession-0.4.9.2-2-x86_64.pkg.tar.xz
[yssd@YS ~]$ cat /etc/slim.conf
# Path, X server and arguments (if needed)
# Note: -xauth $authfile is automatically appended
default_path /bin:/usr/bin:/usr/local/bin
default_xserver /usr/bin/X
xserver_arguments -nolisten tcp vt07

# Commands for halt, login, etc.
halt_cmd /sbin/shutdown -h now
reboot_cmd /sbin/shutdown -r now
console_cmd /usr/bin/xterm -C -fg white -bg black +sb -T "Console login" -e /bin/sh -c "/bin/cat /etc/issue; exec /bin/login"
#suspend_cmd /usr/sbin/suspend

# Full path to the xauth binary
xauth_path /usr/bin/xauth

# Xauth file for server
authfile /var/run/slim.auth


# Activate numlock when slim starts. Valid values: on|off
numlock on

# Hide the mouse cursor (note: does not work with some WMs).
# Valid values: true|false
# hidecursor false

# This command is executed after a succesful login.
# you can place the %session and %theme variables
# to handle launching of specific commands in .xinitrc
# depending of chosen session and slim theme
#
# NOTE: if your system does not have bash you need
# to adjust the command according to your preferred shell,
# i.e. for freebsd use:
# login_cmd exec /bin/sh - ~/.xinitrc %session
login_cmd exec /bin/bash -login ~/.xinitrc %session

# Commands executed when starting and exiting a session.
# They can be used for registering a X11 session with
# sessreg. You can use the %user variable
#
# sessionstart_cmd some command
# sessionstop_cmd some command

# Start in daemon mode. Valid values: yes | no
# Note that this can be overriden by the command line
# options "-d" and "-nodaemon"
# daemon yes

# Available sessions (first one is the default).
# The current chosen session name is replaced in the login_cmd
# above, so your login command can handle different sessions.
# see the xinitrc.sample file shipped with slim sources
sessions xfce4,icewm-session,wmaker,blackbox

# Executed when pressing F11 (requires imagemagick)
screenshot_cmd import -window root /slim.png

# welcome message. Available variables: %host, %domain
welcome_msg Welcome to %host

# Session message. Prepended to the session name when pressing F1
# session_msg Session:

# shutdown / reboot messages
shutdown_msg The system is halting...
reboot_msg The system is rebooting...

# default user, leave blank or remove this line
# for avoid pre-loading the username.
default_user yssd

# Focus the password field on start when default_user is set
# Set to "yes" to enable this feature
#focus_password no

# Automatically login the default user (without entering
# the password. Set to "yes" to enable this feature
auto_login yes


# current theme, use comma separated list to specify a set to
# randomly choose from
current_theme default

# Lock file
lockfile /var/lock/slim.lock

# Log file
logfile /var/log/slim.log

---------------------------------
$ cat .xinitrc
#!/bin/sh
#
# ~/.xinitrc
#
# Executed by startx (run your window manager from here)

export GTK_IM_MODULE=fcitx
export QT_IM_MODULE=fcitx
export XMODIFIERS="@im=fcitx"

if [ -d /etc/X11/xinit/xinitrc.d ]; then
for f in /etc/X11/xinit/xinitrc.d/*; do
[ -x "$f" ] && . "$f"
done
unset f
fi

exec startlxde

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