Graphical User Interfaces in Linux

GNOME/KDE/X-window system

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– X-window system

. It is the main GUI component of linux.

. It is based on client/server Architechure.

. Applications are called x-clients & display is called x-server.

. x-cleints communicates with x-server using x-protocol.

. x window system was developed by Athena project of MIT; now handled by

xc-consortium.

. It is plateform independent.

. It should not be pluralized.

GNOME (global network object model environment)

. It is default & consistent desktop environment.

. It has been developed using GTK toolkit.

KDE (K Desktop environment)

. It is also consistent desktop environment of Redhat Linux.

. It has been developed using QT-toolkit.

Window Managers

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– Metacity – GNOME window manager

KWM – KDE

-Display Manager (GUI login screen)

#runlevel

N 5 (current runlevel)

1= single user mode

3- only text-based terminals (f1-f6) are available

5 – both text-based terminals ( f1-f6) & GUI (f7) are available

to switch level

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#init <runlevel> to switch into the specified runlevel

eg. #init 5

To add runlevel at system startup

open

# vi /etc/inittab

change

id:5:initdwefault:

change 5 into 3 or desired

to logout from GUI mode

press ALT+CTRL+<backspace>

GDM= GNOME display manager

XDM= xfree86 ,, ,,

to change display manager

—————————

#vi /etc/sysconfig/desktop

DESKTOP=”GNOME”

remove above desktop=”gnome” line and add following

DISPLAYMANAGER=”GNOME”

“KDE”

“XDM”

-Desktop switching load

14 June 05 RHCE Preparation Course

GNOME/KDE/X-windows system (Contd..)

GNU Applications

* GUI Terminals

#gnome-terminal – gnome terminal

#konsole – KDE

#xterm – XFree86

* GUI Editors

#gedit – GNOME Editor

#kwrite – KDE

#gvim – GUI version of vi

#xemacs – ,, ,, ,, emacs

* Web Browsers

#mozilla – standard web browser

#konqueror – KDE ,, ,, ,,

#nautilus – Web browser/file manager

* Email Clients

#Mozilla Mail – Standard email client

#kmail – KDE ,, ,, ,,

#evolution – Gnome ,, ,,

* Office Applications

#office.org Office suit

#oowriter – word processing application

#oocalc – Calculator

#ooimpress – Presentation software etc…..

* Some more GNOME applications

#gnumeric – Spread sheet

#mrproject – Project management software

#gnomemeeting – Video conferencing software