intro unix/linux 12

Lesson 12-Accessing and Exploring Graphical Desktops

Overview

The UNIX/Linux graphical desktop.

Starting the X Window system from a terminal.

Exploring the graphical desktop environment.

The UNIX/Linux Graphical Desktop

UNIX and Linux support both graphical and character-based

terminals.

GNOME (GNU Network Object Model Environment) and KDE (K

Desktop Environment) are the two most popular flavors of the

graphical desktop.

The X Window system is the fundamental graphical tool that

enables particular desktop window managers such as GNOME

and KDE to operate.

Starting the X Window System from a Terminal

Launching X Window system from Linux:

The “startx” command starts the fundamental graphics

program, the X Window system, and then launches your

account’s default window manager.

A desktop with icons, menu bar, and an active mouse is

displayed.

The startx utility flags an error if X Windows is not properly

installed.

Starting the X Window System from a Terminal

Launching X Window system from UNIX:

In UNIX environment, the “xinit &” command starts the

fundamental graphics program, the X Window system.

A full graphical desktop environment is displayed once the X

Window session is started.

Starting the X Window System from a Terminal

Launching X Window system from UNIX (continued):

The "gnome &" or the "kde &" command can be used for

selecting a particular graphical interface or desktop.

The Motif Window Manger ("mwm &") or the blackbox

"blackbox &" desktop program can also be started.

Exploring the Graphical Desktop Environment

A generic GNOME desktop

Exploring the Graphical Desktop Environment

Navigating the Task Bar.

Accessing applications through the Main Menu.

Moving, resizing, and iconifying Windows.

Starting programs with icons.

Exploring the Graphical Desktop Environment

Using the menu bar.

Customizing the desktop environment.

Exiting a session from the desktop.

Navigating the Task Bar

The Task Bar, by default, appears at the bottom of the

desktop.

In the GNOME and KDE interface, various icons on the

desktop allow a user to access the Terminal Emulator, Help,

web browser, and other features.

The Task Bar contains a wide variety of configurable

settings and features.

Navigating the Task Bar

The Terminal Emulator or the Console icon opens a terminal

window where shell commands can be executed.

Multiple terminal windows can be created on the screen to

work in two or more environments at the same time.

A terminal window uses a default font unless the –fn option

has been specified.

Navigating the Task Bar

The r16 and r24 font can be used for configuring the font

size.

The Task Bar also contains a set of four clustered buttons

that allows a user to switch to an alternate desktop.

Accessing Applications through the Main Menu

The Main Menu in GNOME or the Start Application in KDE

pops up a menu that provides access to various programs,

utilities, settings, and other system menus.

The Main Menu provides access to various programs and

utilities for working, like spreadsheets, address book, word

processor, calculator programs, games, etc.

Moving, Resizing, and Iconifying Windows

The window manager interprets mouse clicks and drags in

the usual ways.

The handle on the sidebar of the window allows the window

to be reshaped.

The minimize button is located at the top-right corner of the

window, and is represented in the form of an underscore.

Moving, Resizing, and Iconifying Windows

The icon of the active window is placed at the center of the

Task Bar.

A Help or Documentation browser is an interface to the

various forms of documentation on the computer as well as

the Internet.

A web browser such as Netscape, Mozilla, or Galeon is usually

included with X Windows and can be accessed either through

the Task Bar or the Main Menu.

Starting Programs With Icons

The icons on the desktop can be customized or removed

according to the user’s preferences.

The Trash icon in the desktop is similar to a Recycle bin and

can be used for recovering documents that get accidentally

deleted.

The “Empty Trash” option deletes the files permanently

from the system.

Using the Menu Bar

The menu bar has functions like a quick reference location for

frequently used applications, configurations, and even

favorite web sites.

Application, Utilities, Development, and Games are some of

the topics that appear in the drop-down menu when the

Programs icon on the Task Bar is clicked.

A web page saved as favorites in the browser also appears for

quick reference.

Customizing the Desktop Environment

The appearance of the desktop can be easily changed with

the help of the pop-up menu that appears when the mouse is

right-clicked on the desktop.

The screen saver and various other options can be configured

with the help of the Main Menu.

X Windows also allows shortcuts to be created on the desktop

for frequently used programs with a simple drag-and-drop

operation.

Exiting a Session From the Desktop

A desktop session in GNOME can be exited by using the

Main Menu, while in KDE, the Start Application is used to

achieve the same.

The “Lock Screen” option keeps the current session alive,

but requires the user to provide a password to unlock the

screen.

The “Logout” option can be selected either from the pop-up

menu that appears when the desktop is right-clicked, or

from the Main Menu.

Exiting a Session From the Desktop

Summary

In UNIX and Linux, the X Window system provides users

with a full graphical environment.

Login accounts can be configured to start up in the

graphical or terminal mode.

In the graphical desktop, the dashboard, or Task Bar,

provides a series of menus and icons for easy access to

programs.