====== X.Org ======

[[http://www.x.org/|The X.Org]] project provides an open source implementation of the [[wp>X Window System]].
===== The simplest working config (th) =====
The shortest way to working xorg with mouse and keyboard for common hardware configurations: 

<file># backup xorg.conf, and then
rm /etc/X11/xorg.conf
# install drivers
poldek -u xorg-driver-video-$YOUR_VIDEO_DRIVER
poldek -u xorg-driver-input-evdev
# install hal and dbus
poldek -u hal dbus
# and the most important step for mouse and keyboard (-:
service messagebus start
service haldaemon start
# test it
Xwrapper
</file>


===== xserver >= 1.5.3 and kbd + mouse drivers + no HAL =====
xorg server can use two different sources of mouse, keyboard information. This section descibed kbd and mouse driven one without a HAL (or with disabled HAL). 

xorg.conf, section "''ServerLayout''": 

<file># disable HAL
Option "AutoAddDevices" "false"

# indirectly cause kbd & mouse driver to be used
Option  "AllowEmptyInput" "false"
</file>
You need typical keyboard and mouse configuration sections, too. 



===== xserver 1.8+ and input devices + udev =====
Hal is no longer used. See [[https://wiki.ubuntu.com/X/Config/Input#Input|https://wiki.ubuntu.com/X/Config/Input#Input]] 

NOTE: **xinput** is in **xorg-app-xinput** package in PLD Linux. 



==== xserver 1.8+ and keyboard ====
Configuration stored in '/etc/X11/xorg.conf.d/10-keyboard.conf' supposed to support pl national characters and ctrl-alt-bkspc. Missing ctrl-alt{-,+}) though. 

<file>Section "InputClass"
        Identifier "keyboard-all"
        Driver "evdev"
        Option "XkbLayout" "us,pl"
        Option "XkbModel" "evdev"
        Option "XkbVariant" ",qwerty"
        #Option "XkbOptions" "grp:alt_shift_toggle,grp:switch,compose:rwin,terminate:ctrl_alt_bksp"
        Option "XkbOptions" "compose:rwin,terminate:ctrl_alt_bksp"

        Option          "LeftAlt"       "Meta"
        Option          "RightAlt"      "ModeShift"

        MatchIsKeyboard "on"
EndSection
</file>


==== xserver 1.8+ and synaptics ====
Consider creating file '/etc/xorg.conf.d/10-synaptics.conf' containing: 



<file>Section "InputClass"
        Identifier      "touchpad catchall"
        Driver          "synaptics"
        MatchIsTouchpad "on"
        MatchDevicePath "/dev/input/event*"
        Option          "SHMConfig"             "true"
        Option          "HorizEdgeScroll"       "1"
        Option          "VertEdgeScroll"        "1"
        Option          "TapButton1"            "1"
        Option          "TapButton2"            "1"
        Option          "TapButton3"            "1"
        Option          "AccelFactor"           "0.001"
EndSection
</file>


===== xserver and evdev driven input devices + HAL =====
xorg server can use two different sources of mouse, keyboard information. This one is anount evdev driven and HAL provided information.  

evdev kernel module needs to be loaded: 

<file>echo evdev >> /etc/modules
modprobe evdev
</file>
xorg.conf: 

<file>Section "InputDevice"
        Identifier  "Keyboard0"
        Driver      "kbd"
        Option "XkbRules"   "xorg"
        Option "XkbModel"   "evdev"
        Option "XkbLayout"  "pl"
EndSection
</file>
**Keyboard configuration** 

Manual: 

<file>cp -a /usr/share/hal/fdi/policy/10osvendor/10-keymap.fdi /etc/hal/fdi/policy/
vi /etc/hal/fdi/policy/10-keymap.fdi
</file>
If the above does not work: 

<file>setxkbmap -model evdev -layout pl
</file>
From KDE 3 Control Center: 

<file>Control Center -> Regional & Accessibility -> Keyboard Layout -> Keyboard model: "Evdev-managed keyboard"
</file>
From KDE 4 systemsettings: 

<file>System settings -> Regional & Language -> Keyboard Layout ->  Keyboard model: "Evdev-managed keyboard"
</file>
Note that kde3/4 method above is just a GUI-way for configuring kde setxkbmap call. 



===== synaptics and mouse tapping =====
**WARNING**: do not add any kind of synaptics entries to xorg.conf. If you do, xorg will see two of them -- the manually-added one and the automatically-detected one (type //xinput list// to see a list of all detected input devices) and all of the configuration options listed below will get applied to the **wrong** one. In other words, as long as there's a synaptics entry in xorg.conf, you won't have any way to change the drivers configs. 

Xorg v7.4 does not enable tapping by default. To enable add to 11-x11-synaptics.fdi: 

<file><merge key="input.x11_options.TapButton1" type="string">1</merge>
<merge key="input.x11_options.TapButton2" type="string">2</merge>
<merge key="input.x11_options.TapButton3" type="string">3</merge>
</file>
NOTE: you need to [[http://www.archlinux.it/wiki/index.php?title=Xorg_input_hotplugging#Configuration|copy]] it first, if you haven't done it so: 

<file>cp -a /usr/share/hal/fdi/policy/10osvendor/11-x11-synaptics.fdi /etc/hal/fdi/policy
</file>
You may find these also useful (if your hardware supports): 

<file><merge key="input.x11_options.VertEdgeScroll" type="string">true</merge>
<merge key="input.x11_options.CircularScrolling" type="string">true</merge>
</file>
More from [[http://www.archlinux.it/wiki/index.php?title=Touchpad_Synaptics|archlinux wiki]]. 



===== 100% CPU usage when using xdm (kdm, gdm) and SysVinit (not upstart-SysVinit) =====
The problem is that when xdm runs with recent X server then tty0 (as it's first free tty) is taken by xserver. Then when [[:SysVinit|SysVinit]] tries to run mingetty also on tty0. This ends with mingetty fighiting with X server for tty0. 

upstart-Sysvinit is not affected as it starts mingetty before xdm runs, so xdm choses different, first free ttyX. 

Solution: change xdm to use fixed tty that's not used in inittab for mingettys (like tty9). 



===== xorg-driver-video-intel >= 2.9.99.0 requires KMS =====
Latest Intel xorg drivers require KMS (kernel mode setting) to be active. Run kernel >= 2.6.31 and set in /etc/sysconfig/geninitrd: 

<file>PREMODS="intel-agp i915"
</file>
and regenerate geninitrd. 

Alternatively run: 

<file>modprobe i915
</file>


===== XDMCP =====
If you want to create cross computer X sessions using XDMCP please enable it *dm (kdm, gdm) on machine you wish to connect to. 

Now you can run: 

<file> X -query xdmcp.enabled.server
</file>
or just  X or local kdm and select network log in instead of local log in. 



==== Source IP# number problem on client machine ====
Rules which X selects interface on which it binds for X sessions are not clear for some people. If you spot problem :  

<file>XDMCP fatal error: Session failed Session <some_number> failed for display my.adress.not.acessible.to.server:0: cannot open display
</file>
Try if forcing connection source ip adress helps: 

<file> X -query xdmcp.enabled.server  -from  my.adress.acessible.to.server
</file>