.. -*- coding: utf-8; -*-

====

 X.

====

.. contents::

   :local:

Standard.

=========

See

  http://www.tronche.com/gui/x/icccm/

Widget toolkit.

===============

  http://en.wikipedia.org/wiki/Widget_toolkit

                Widget toolkit

  http://en.wikipedia.org/wiki/List_of_widget_toolkits

                List of widget toolkits

GTK+.

-----

  http://en.wikipedia.org/wiki/GTK%2B

QT.

---

  http://en.wikipedia.org/wiki/Qt_%28toolkit%29

WxWidgets.

----------

  http://en.wikipedia.org/wiki/WxWidgets

Tk.

---

  http://en.wikipedia.org/wiki/Tk_%28computing%29

FLTK.

-----

  http://en.wikipedia.org/wiki/FLTK

Xaw.

----

  http://en.wikipedia.org/wiki/Xaw

GNUstep.

--------

  http://en.wikipedia.org/wiki/GNUstep

XView.

------

  http://en.wikipedia.org/wiki/XView

Getting info about X window and X-related applications data.

============================================================

Look for system registered resources::

  $ listres

  $ listres -all

  $ appres XTerm

  $ appres -name htop   # for xterm with running bash inside

Look for X resources of running applications::

  $ xprop -root

  $ xprop -name bash    # for xterm with running bash inside

Keyboard's keys under X window.

===============================

  scancodes

                hardware-dependent codes generated by keystrokes and received by

                the X server.

  keycodes

                Codes sent by the X server to the client indicating which key

                was pressed. Keycodes by themselves do not indicate what the

                keystroke means; the client must request that information from

                the X server.

  modifiers

                Flags, such as ``shift`` and ``control``, that the server sends

                with each keycode to the client. The client's interpretation of

                the keycode may depend on the state of the modifiers. For

                example, the state of the shift modifier determines whether an

                alphabetic character should be lowercase or uppercase. Because

                the X server encodes the states of the eight modifiers (shift,

                lock, control, mod1, mod2, mod3, mod4, and mod5) in a single

                byte of data, modifiers are often referred to as ``modifier

                bits``.

  keysyms

                codes that specify the glyphs appearing on the keys. The X

                server also maintains a list of strings that describe the

                keysyms, such as ``a``, ``B``, and ``Control``.

Find the keycode.

=================

::

  $ xev

  $ xev | grep keysym --color

  $ cat /usr/include/X11/keysymdef.h

Don't run under X::

  $ showkey

To do same under X::

  $ xev | sed -n 's=.*keycode \([0-9]*\).*=\1=p'

List key modifier (like ``shift``/``control``/``meta``/``mod2``)::

  $ xmodmap -pm

Add keycode to modifier::

  $ xmodmap -e "add shift = Shift_R"

Remove keycode from modifier::

  $ xmodmap -e "remove shift = Shift_L"

Examining the current keymap table::

  $ xmodmap -pk

Changing the keymap table::

  $ xmodmap -e "keycode 34 = bracketleft braceleft"

  $ xmodmap -e "keysym CapsLock = Control_L"

  https://wiki.ubuntu.com/LaptopTesting/Keycodes

                Ubuntu Keycodes howto.

  http://en.gentoo-wiki.com/wiki/Multimedia_Keys

                Gentoo Multimedia Keys howto.

List input devices.

===================

::

  $ xinput -list

You can use obtained ID in such command::

  $ setxkbmap -device $ID -layout dvorak

Making screenshort.

===================

::

  $ sudo apt-get install scrot

  $ scrot -d <sec> <file>

or::

  $ sudo apt-get install imagemagic

  $ import -quality 100 -pause <sec> -silent <file>

Input method.

=============

Input method by setxkbmap.

--------------------------

::

  $ setxkbmap ru

  $ setxkbmap -rules xorg -model pc104 -layout "us,ru" -option "grp:rwin_toggle,grp_led:scroll" -variant ",winkeys"

Input method from xorg.conf.

----------------------------

::

  Section "InputDevice"

      Identifier     "Keyboard0"

      Driver         "kbd"

      Option         "XkbModel" "pc105"

      Option         "XkbLayout" "us,ru"

      Option         "XkbVariant" ",winkeys"

      Option         "XkbOptions" "grp:rwin_switch,grp_led:scroll"

  EndSection

.Xdefaults

==========

The syntax of an Xdefaults file is as follows::

  [client. | *][{restriction.} | *]resource: value

where:

  client

                The name of the application, some program allow change it by

                '-name' option. This element is optional (can be substituated

                with wildcard).

  restriction

                Class names or name of specific class instance. The classes

                names conventionally start with an upper-case letter.

  resource

                The name of the resource whose value is to be changed.

                Resources are typically lowercase with uppercase

                concatenation.

  value

                The actual value of the resource.

  delimiters

                A period (.) is used to signify each step down into the

                hierarchy. A colon (:) is used to separate the resource

                declaration from the actual value.

Comment start with '!' char and goes up to end of line or C-like ``/* */``.

Use xprop utility to find classes and resources used by application.

To reread your .Xresources file, and throw away your old resources::

  $ xrdb ~/.Xdefaults

To reread your .Xresources file, and keep your old resources::

 $ xrdb -merge ~/.Xdefaults

Example::

  *foreground: yellow

  XClock*foreground: pink

  Xman*topBox*foreground: blue

String value type.

------------------

This can be path specification like '/usr/bin/firefox'.

Colors value type.

------------------

For color names see '/usr/lib/X11/rgb.txt'. Also you can use hex

representation #ffffff.

Font value type.

----------------

You can use either a full name, a wildcarded specification, or a font alias::

  XTerm*Font: -adobe-courier-bold-r-normal--14-140-75-75-m-90-iso8859-1

  XTerm*Font: *courier-bold-r*140*

  XTerm*Font: 7x14

Geometry value type.

--------------------

  XCalc*geometry: 120x120-0-0

  XClock*geometry: -50+100

Cursor names value type.

------------------------

Cursor resources require the name of the file in /usr/include/X11/bitmaps that

contains the cursor you want to use.

  ScoTerm*pointerShape: gumby

Pixmaps value type.

-------------------

Pixmaps are patterns, like bitmaps, that are used to texture or color an area

on your display. Pixmap resources are specified like cursors or bitmaps.

Numebers value type.

--------------------

  XLogo*borderWidth: 10

Boolean value type.

-------------------

Some resources require a boolean value, such as 'true' or 'false', 'yes' or

'no', or 'on' or 'off'.

Wildcard matching.

------------------

The asterisk can be used as a wildcard, making it easy to write a single rule

that can be applied to many different applications or elements.

X utilities.

============

  appres

                List "application resources".

  listres

                List resources in widgets.

  bitmap, atobm, bmtoa

                Bitmap editor and converter utilities.

  editres

                Dynamic resource editor for X Toolkit applications.

  iceauth

                ICE authority file utility.

  xauth

                X authority file utility.

  ico

                Animate an icosahedron or other polyhedron.

  luit

                Locale and ISO 2022 support for Unicode terminals.

  setxkbmap

                Set the keyboard using the X Keyboard Extension.

  x11perf

                X11 server performance test program.

  x11perfcomp

                X11 server performance comparison program.

  xcalc

                scientific calculator desktop accessory that can emulate a TI-30

                or an HP-10C.

  xclock

                Displays the time in analog or digital form.

  xconsole

                Monitor system console messages with X.

  xdpyinfo

                displaying information about an X server.

  xev

                "Event Tester" window.

  xeyes

                Showing two googly eyes which follow the cursor movements on the

                screen as if they were watching it.

  xfontsel

                Point and click selection of X11 font names.

  xgamma

                Alter a monitor's gamma correction through the X server.

  xhost

                Server access control program for X.

  xinit

                X Window System initializer.

  startx

                Initialize an X session.

  xkill

                Kill a client by its X resource.

  xload

                System load average display for X.

  xlogo

                X Window System logo.

  xlsclients

                listing information about the client applications running on a display.

  xmag

                Magnify parts of the screen.

  xman

                Manual page display program for the X Window System.

  xmessage

                Display a message or query in a window.

  xmodmap

                Utility for modifying keymaps and pointer button mappings in X.

  xmore

                Plain text display program for the X Window System.

  xprop

                Property displayer for X.

  xrandr

                Primitive command line interface to RandR extension.

  xrdb

                X server resource database utility.

  xrefresh

                Refresh all or part of an X screen.

  xset

                User preference utility for X.

  xsetmode

                Set the mode for an X Input device.

  xsetpointer

                Set an X Input device as the main pointer.

  xsetroot

                Root window parameter setting utility for X.

  xsm

                X Session Manager

  resize

                Set environment and terminal settings to current xterm window size.

  xterm

                Standard terminal emulator for the X Window System.

  xvinfo

                Print out X-Video extension adaptor information.

  xwd, xwud

                Useful and easy way to take screenshots. Saves in the XWD X

                Window Dump image data format.

  xwininfo

                Window information utility for X.

XText extension.

================

``xdotool`` and ``xautomation`` utilities use ``XText`` for emulating user

actions.

GLX info.

=========

To determine whether 3D acceleration is working::

  $ apt-get install mesa-utils

  $ glxinfo | grep render

To see how many frames per second your video card is putting out::

  $ glxgears -info

See:

  https://wiki.debian.org/Mesa

                Mesa is an open source 3D computer graphics library that

                provides a generic OpenGL implementation for rendering

                three-dimensional graphics on multiple platforms.

Running a secondary X server.

=============================

::

  $ startx xterm -- :$N -depth 16

New server will be accessible at ``Alt+Ctrl+F$((N+6))``::

  :0  Alt+Ctrl+F7

  :1  Alt+Ctrl+F8

  ...

  :5  Alt+Ctrl+F12

In order to fix::

  X: user not authorized to run the X server

run::

  $ sudo dpkg-reconfigure x11-common

Running X server without display.

=================================

Run ``Xvfb`` and make screenshort of desktop::

  $ apt-get install xvfb

  $ Xvfb :1 -screen 0 1280x1024x24 &

  $ xclock -display :1 &

  $ import -display :1 -window root image.png

  $ kill %1 %2

In order to run ``Xvfb`` permanently add entry to ``/etc/inittab``::

  xvfb:2:respawn:/usr/bin/Xvfb :1 -ac -screen 0 1280x1024x24

Running X server in nested windows.

===================================

::

  $ sudo apt-get install xnest

  $ startx xterm -- `command -v Xnest` :1 -geometry 800x600

Running X server under Windows

==============================

https://sourceforge.net/projects/vcxsrv/

  VcXsrv Windows X Server, the xorg git sources compiled with Visual C++ 2012

  Express Edition.

http://x.cygwin.com/

  Cygwin's xwin. Cygwin/X is a port of the X Window System to the Cygwin API

  layer for the Microsoft Windows family of operating systems.

https://sourceforge.net/projects/xming/

  Xming is the leading X Window System Server for Microsoft Windows 8/7/Vista/XP

  (+ server 2012/2008/2003). It is fully featured, small and fast, simple to

  install and because it is standalone native Microsoft Windows, easily made

  portable (not needing a machine-specific installation).