The X Window System Overview

The X Window System Overview

1

CHAPTER 1

INTRODUCTION

1.1 Background

The Linux operating system today becomes the great choices, for

everything requirement or platform. In Linux many features is offered, such as

graphical or GUI, internetworking, word processing and many others. And in this

case, we will explain the X Window System about GUI that was released in 1984.

The main features of X Window System are: modularity, extensibility and

interoperability. The X Window System uses client-server architecture.

The X server (the Xorg binary) listens for connections from X client

applications via a network or local loopback interface and X client applications

exist in the user-space, creating a graphical user interface (GUI) for the user and

passing user requests to the X server. In this case, writers will tell about historical

X Window System, the features of X Window System, Configuration file server,

and comparison between X Window System with X Windows System, in order to

reader know about it.

1.2 Problem Formulation

In this paper we can get the problem that will be formulated inside the

explanation later, they are:

1. What are the histories of X Window System in Linux?

2. What are the features of X Window System?

3. What are the configuration files of X Window System?

4. What are the ways to differ of the X Windows System and X Window

System?

1.3 Purpose

Our purposes in creating this paper are:

1. To inform the history of X Window System.

2. To give the understanding of X Window System in Linux includes

features of it.

3. To give the ways to set configuration files of X Window System.


2

1.4 Benefit

We can get some benefit for explaining this paper, some of them are:

1. Makes the GUI and application more user friendly to the user.

2. Knows the features of X Window System.

3. Knows the ways to set configuration files of X Window System.

1.5 Problem Boundaries

In this paper we just explain about the historical of the X Window System

includes the features of it. And also the configuration files of X Window System

especially for the server configuration file, the comparison of X Window System

and X Window System as well.

1.6 Writing Systematic

This is the complete writing systematic:

CHAPTER I INTRODUCTION

This chapter explains about background, problem formulation, purpose

benefit, problem boundaries and writing systematic in creating ISAS.

CHAPTER II CONTENT

This chapter explains about the content of ISAS.

CHAPTER 3 ANALYSIS

This chapter explains about the comparison between X the Window

System and the X Window System.

CHAPTER 4 CLOSING

This chapter explains about conclusion and suggestion.

BIBLIOGRAPHY


3

1.7 Time Schedule

Table 1.1 Time Schedule

No Activities January 2009

1 2 3 4 4 5 5 5 7 7

1

Looking of Data

2

Making Abstraction and

Preface

3

Make Chapter I – IV

4

Make Closing

6

Making Slide Show

7

Monitoring


4

CHAPTER 2

CONTENT

2.1 The X Window System

While the heart of Red Hat Enterprise Linux is the kernel, for many users,

the face of the operating system is the graphical environment provided by the X

Window System, also called X.

Other windowing environments have existed in the UNIX world, including

some that predate the release of the X Window System in June 1984. Nonetheless,

X has been the default graphical environment for most UNIX-like operating

systems, including Red Hat Enterprise Linux, for many years.

The graphical environment for Red Hat Enterprise Linux is supplied by

the X.Org Foundation, an open source organization created to manage

development and strategy for the X Window System and related technologies.

X.Org is a large-scale, rapidly developing project with hundreds of developers

around the world. It features a wide degree of support for a variety of hardware

devices and architectures, and can run on a variety of different operating systems

and platforms. This release for Red Hat Enterprise Linux specifically includes the

X11R7.1 release of the X Window System.

2.2 The Main Featured of X Window System Is:

1. Modularity

Modularity refers to the phenomenon of being independent. The modular

applications consist of various modules. Because each module is independent of

the other, you can test and implement each module independently. The modularity

featured is used when you need to develop applications that require various

components, each providing a different functionality to the applications.

X Window System consists of various components that can be installed

and used separately. If the function of a particular component changes, it affects

only that particular component and the application in which it is used. In addition,

you can upgrade a particular version of an application without affecting the other

applications that work in coordination with the application you are upgrading.


5

2. Extensibility

Extensibility is the ability of a system to enhance its functionality by

incorporating new features. The developers of X Window System anticipated the

need to incorporate new and advance features to enhance the existing features of

X Window System. Moreover, as a particular product is enhanced, other products

that work in coordination with also need to be enhanced to match the performance

level.

To make X Window System extensible, a set of libraries have been

provided. These libraries are called the extensions of X Window System. These

extensions allow X Window System to incorporate the changes. The extensions

are:

1. SHAPE: provides extensions for the nonrectangular windows. The

application windows are rectangular by default. Nonrectangular windows

have circular corners instead of angular.

2. Digitally Phase Modulated Signals (DPMS)

3. Xinerma

4. Graphics Library X (GLX)

5. Long Bandwidth X (LBX)

6. Differential Graded Algebra (DGA)

3. Interoperability

Interoperability is the ability of X Window System to support various

hardware platforms and physical networking media. X Window System offers the

following features to incorporate interoperability:

Network Transparency.

Network Independency.

Hardware Independency.

Comprehensive display capabilities.


6

2.3 Installation of X Window System

Before installing X Window System in Linux, we should know the

minimum requirements for outgoing the computer run properly, they are:

1. Processor minimal in Pentium 233 MMX

2. RAM minimal 32 MB

3. Hard disk minimal has free space about 100 MB

4. Graphic card SVGA with memory minimal 1 MB yang

5. Supported XFree86-3.3.6

6. Mouse and keyboard which supported XFree86-3.3.6

In CD distribution of Linux Red Hat consists of files with the prefix X,

such as XFree86. These files will build the X Window System in your Linux. The

desktop environments and other supported applications is assigned as rpm file

with the prefix K or k for KDE and G or GNOME. Version of XFree86 that is

offered is version 3.3.6. The way to install is easy; you just run the console to

install X Window System by selecting the packet that needed automatically using

command (rpm -ivh XFree86-3.3.6-20.i386.rpm).

2.4 Understanding the X Client and X Server

X windows system is based on the client/server architecture, includes two

primary components, X server and X client. The X server called also XFree86

Server. Program that enables various applications, called the X client, which run

on Linux system to display their GUI components. The configuration files of the

X client and X server stored in /etc/X11 and /usr/X11R6. The /etc/X11 directory

contains the X Server application and X client configuration files. The

/usr/X11R6 contains the X client application and X server configuration files.

And inside this directory contains the software required to support the x client and

x server, they are.

a. /usr/x11R6/bin : Contains X server and various X client

b. /usr/x11R6/include : contains the file required to develop X client and GUI

graphic, such as icon.

c. /usr/x11R6/lib : contains the software libraries required to support the X

server and client.


7

d. /usr/x11R6/lib/x11 : contains the system resource, default X client

resource, and documentation files.

e. /usr/x11R6/lib/module : contains various drivers and X server module to

enable the various graphic card.

f. /usr/x11R6/lib/man : contains the subdirectory that consists of manual

page on X window programming and X client.

Picture 2.1 The Connection between Client and Server

The X server and X client can run on the same and different systems. The

X client sends the display request to the X server and interacts with the various

hardware devices of the system to respond to the request of the X client. In

addition, the X server performs the following functions:

1. Displays the error that occur when the X client make a request for display

2. Controls the I/O devices.

3. Directs the keyboard and mouse input to the desired X client or any event

on the network.

4. Manages the windows displayed on the screen

In other case, we can get the key functions of the X client that enables

many task offered in a system, they are:

1. Requests the server for various services.

2. Accepts events in response to the requests from server.

3. Accepts error messages from the server.


8

The following example gives an insight on the client/server architecture of

X Window System. When the hardware event, such as a key press, occurs, the X

server receives the information. The server passes this information to the client

application. The client processes the received information and sends a request to

the server.

The usefulness of X Window System may not be felt if the client and the

server are present on the same computer. The potential of the client/server

architecture is realized when it is used across the network on multiple computer.

But, many advantages of using the X Windows System in X server/client

architecture, they are:

1. Can install the client and server software in different computers.

2. Can port the X client applications or other platform.

3. There can be multiple X servers running on more than one computer at

a time.

2.5 The X Server/Client Configuration Files

The X server is a single binary executable ( /usr/bin/Xorg ). Associated

configuration files are stored in the /etc/X11/ directory ( as is a symbolic link — X

— which points to /usr/bin/Xorg ). The configuration file for the X server is

/etc/X11/xorg.conf.

The X Window System uses a client-server architecture. The X server (the

Xorg binary) listens for connections from X client applications via a network or

local loopback interface. The server communicates with the hardware, such as the

video card, monitor, keyboard, and mouse. X client applications exist in the user-

space, creating a graphical user interface (GUI) for the user and passing user

requests to the X server.

The directory /usr/lib/xorg/modules/ contains X server modules that can be

loaded dynamically at runtime. By default, only some modules in

/usr/lib/xorg/modules/ are automatically loaded by the X server. To load optional

modules, they must be specified in the X server configuration file,

/etc/X11/xorg.conf.


9

2.5.1. Runlevel 3

When in runlevel 3, the best way to start an X session is to log in and type

startx. The startx command is a front-end to the xinit command, which launches

the X server (Xorg) and connects X client applications to it. Because the user is

already logged into the system at runlevel 3, startx does not launch a display

manager or authenticate users.

When the startx command is executed, it searches for the .xinitrc file in

the user's home directory to define the desktop environment and possibly other X

client applications to run. If no .xinitrc file is present, it uses the system default

/etc/X11/xinit/xinitrc file instead.

After setting these options, the xinitrc script executes all scripts located in

the /etc/X11/xinit/xinitrc.d/ directory. One important script in this directory is

xinput.sh, which configures settings such as the default language.

In the xinitrc script attempts to execute .Xclients in the user's home

directory and turns to /etc/X11/xinit/Xclients if it cannot be found. The purpose of

the Xclients file is to start the desktop environment or, possibly, just a basic

window manager. The .Xclients script in the user's home directory starts the user-

specified desktop environment in the .Xclients-default file. If .Xclients does not

exist in the user's home directory, the standard /etc/X11/xinit/Xclients script

attempts to start another desktop environment, trying GNOME first and then KDE

followed by twm.

2.5.2. Runlevel 5

When the system boots into runlevel 5, a special X client application

called a display manager is launched. A user must authenticate using the display

manager before any desktop environment or window managers are launched.

Depending on the desktop environments installed on the system, three different

display managers are available to handle user authentication.

GNOME — The default display manager for Red Hat Enterprise Linux,

GNOME allows the user to configure language settings, shutdown, restart

or log in to the system.


10

KDE — KDE's display manager which allows the user to shutdown,

restart or log in to the system.

xdm — A very basic display manager which only lets the user log in to the

system.

When booting into runlevel 5, the prefdm script determines the preferred

display manager by referencing the /etc/sysconfig/desktop file. A list of options

for this file is available in this file:

/usr/share/doc/initscripts-<version-number>/sysconfig.txt

Each of the display managers references the /etc/X11/xdm/Xsetup_0 file to

set up the login screen. Once the user logs into the system, the

/etc/X11/xdm/GiveConsole script runs to assign ownership of the console to the

user. Then, the /etc/X11/xdm/Xsession script runs to accomplish many of the tasks

normally performed by the xinitrc script when starting X from runlevel 3,

including setting system and user resources, as well as running the scripts in the

/etc/X11/xinit/xinitrc.d/ directory.

Users can specify which desktop environment they want to utilize when

they authenticate using the GNOME or KDE display managers by selecting it

from the Sessions menu item (accessed by selecting System (on the panel) =>

Preferences => More Preferences => Sessions). If the desktop environment is

not specified in the display manager, the /etc/X11/xdm/Xsession script checks the

.xsession and .Xclients files in the user's home directory to decide which desktop

environment to load. As a last resort, the /etc/X11/xinit/Xclients file is used to

select a desktop environment or window manager to use in the same way as

runlevel 3.


11

CHAPTER 3

ANALISYS

3.1 The Comparison History of GNOME and KDE

KDE (K Desktop Environment) is desktop environment and platform

application development that was built by toolkit Qt from Trolltech. Here, KDE

can be run in many UNIX systems, includes Linux, BSD, and Solaris and there

also found the version KDE for Mac OS X using subsystem X11 and for

Microsoft Windows using tool supported called Cygwin. And the Mascot for this

KDE is a green dragon called Konqi.

3.1 Logo of GNOME 3.2 Logo of KDE

GNOME is a legal desktop from GNOME Project and this is acronym of

GNU Network Object Model Environment, but nowadays, the using of this

desktop is appeared out of date. So, the developer of it mixes many programs that

interoperability with GNOME, and one of them is realized as The GNOME

Desktop. Then, this desktop is combined with other software such as Kernel for

making a complete system, such as distribution of GNU/Linux or Solaris from

Sun Microsystems.


12

3.2 The Comparison of X Window System in GNOME and KDE

1. KDE is single graphic oriented, so that way the view of it suddenly better

than GNOME which has less oriented in the graphical or view, even

GNOME did not leave it anymore.

2. GNOME has characteristic economical memory usage than KDE, so that

way, GNOME is little bit faster than KDE (it is caused of GNOME not

orienting in graphical as like KDE). Once more it is about performance.

3. The utilities of KDE are so complete, so that way, the newbie will say that

KDE is the Operating System. The entire tools for working in a window

based are available, and many other utilities in side of the project will take

part in moving to KDE. GNOME is not only a window manager, but also

system desktop that interoperable within computer and platform. The

performance of GNOME moving better cause of using Common Object

Resource Broker Architecture (CORBA).

4. KDE at glance is better than other, but many user are still confused not

sure for using it because of the Qt license Toolkit is not free. In other hand,

GNOME is more acceptable in the entire world of OpenSource because

GNOME made with Gtk+ toolkit that is free under the OpenSource GNU

License.


13

Picture 3.1 The Screen Shoot of KDE in Mandriva 2009

Picture 3.1 The Screen Shoot of GNOME in Linux Red Hat Enterprise


14

CHAPTER IV

CLOSING

4.1 Conclusion

After explaining about X Window System above, we can get some of the

conclusion for making sharpness in understanding the content and all about our

problem formulation. Here, one of them:

1. the face of the operating system is the graphical environment provided

by the X Window System, also called X.

2. The main features of x Window System are Modularity, Extensibility

and Interoperability.

3. The desktop environments and other supported applications is assigned

as rpm file with the prefix K or k for KDE and G or GNOME.

4. X windows system is based on the client/server architecture, includes

two primary components, X server and X client.

5. The X server called also XFree86 Server. Program that enables various

applications, called the X client, which run on Linux system to display

their GUI components.

6. The directory /usr/lib/xorg/modules/ contains X server modules that

can be loaded dynamically at runtime. By default, only some modules

in /usr/lib/xorg/modules/ are automatically loaded by the X server.

7. To load optional modules, they must be specified in the X server

configuration file, /etc/X11/xorg.conf.

4.2 Suggestion

Here we suggest when using long–distance communication the best

chosen is fiber optic, is more better then coaxial cable for preventing ceresin.

Then on the next arrangement of paper we suggest explain more detail of process

transmitting data, so finally all of transaction that we send are clearly explained.


15

BIBLIOGRAPHY

[1] http://www.redhat.com/docs [January 19 2008]

[2] http://id.wikipedia.org/wiki/KDE [January 19 2008]

[3] http://id.wikipedia.org/wiki/GNOME [January 19 2008]

[4] http://en.wikipedia.org/wiki/Comparison_of_X_Window_System

_desktop_environments [January 19 2008]

http://id.wikipedia.org/wiki/KDE

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

Documents

The X Window System Overview