Through The X Window

If you installed NetBSD from last months CD, one of your first thoughts, after the euphoria and joy of having installed it correctly has passed must have been, "it's not much to look at is it?" Well this month we're going to rectify that situation. Although all Unix's, including NetBSD are heavily text based operating systems there is a "Windowing System" known as the "X Windowing System" or more simply "X" available.

Despite it's simple name X is a very complex package providing hardware independent retargetable graphics. X works by running what is known as an X server on your desktop machine. The X server does not actually add a Graphical User Interface to your machine, it simply provides an mechanism for other graphical applications to talk to your computer. Running on top of the X server you will need a Window Manger. This controls the look and feel of the desktop environment. There are many different Window Managers available, including ones to make your desktop look like that of a Mac, a Windows 95 PC or even an Amiga. The amiga distribution of X includes 2 Windows managers FVWM and CTWM.

Starting X will launch both the X-server and a windows manager, usually FVWM by default, which will produce a screen much like the one illustrated. Pressing the left mouse over the background will produce a menu of applications. Not all of these are included with the X11 distribution so you will be unable to run all of them. The right mouse button produces another menu listing current running programs allowing you to easily switch between them. Pressing the left mouse button over the close gadget in the top left hand corner of each window produces a menu which allows you to minimise, close or kill that particular window.

The default installation opens two windows at startup, an Xconsole and an Xterm. The Xconsole is NetBSD's message window. You will find you can't use it to type commands into, instead NetBSD will print any system messages in this window. This enables you to keep an eye on what your system is doing at all times without it interfering with what you are doing. (If you are not running X and are logged into the console NetBSD will display any messages on your screen). The Xterm is simply a graphical version of the normal NetBSD screen which you can use to enter commands. It is possible, however to run more than one xterm at once allowing you to perform many task easily at the same time.

In the bottom right hand corner of the screen you will see a button bar containing a clock; a CPU meter; a mailbox flag, although no mail client is included and a kill button. The kill button can be used to terminate any programs that you have finished using, however it is usually desirable to exit them in a more normal fashon. Under the button bar are three boxes that represent three virtual desktops. If you have a powerfull enough system these allow you to run many applications at the same time without your display becoming cluttered.

Most of the programs that can utilise a graphical display can be found in /usr/local/X11R6.1/bin, although non-graphical programs can still be run in an xterm. One of the great strengths of X is that an application does not need to be installed on your machine for you to use it. If you are connected to a network with other Unix machines on it you can run an application on a remote machine and instruct it to use your X-server as it's display. This technique is known as "exporting the display". Many large organisations use this feature as it allows them to use cheap, relativly low power PC's as desktop machines but lets the users run high power applications on large expensive Unix workstations hidden away in server rooms. If you are fortunate to have your Amiga on a network with other Unix machines this can give you instant access to a wide range of software, including titles that have never been relased on the Amiga. There is even a version of Windows NT that can export its display to any machine running X, although personally I wouldn't let it anywhere near my Amiga!

Next month we will be taking a look at what applications are available for NetBSD and exactly how we go about installing them and the boys from UK.AmigaSoc.org will have more hints and tips on customising and using NetBSD.

Box-Out Ideas some of the Programs included with the X11 Distribution xcalc - a scientific calculator xedit - a simple text editor xeyes - Puts a pair of eyes on your desktop xlock - Locks the screen until a password is entered xgas - animated simulation of an ideal gas xtetris - tetris for X puzzle - sliding block puzzle game xmessage - leave messages on your desktop xload - graphical CPU usage display note: there are screenshots of most of these apps included

Tip

/tmp is NetBSD`s equivilent of the RAM disk. NetBSD uses a combination of physical RAM and DISK (the swap partition) to create /tmp. /tmp is a good place to use as a scratch pad

Tip

The ~ character can be used to quickly change to any users home directory and is found in many URL`s on the internet. cd ~chrisl has the same effect as cd /export/home/chrisl

Glossary Of Terms
Console	On multiuser machines each user is expected to work at a distance from the machine on a destop PC or vt100 terminal, and communicate via a network. The console is the monitor that is directly connected to the machine. It is usually only used for maintanance and displaying errors. On machines with no network there is no choice but to work at the console
vt100	A text only data terminal. Essentially it is little more than a screen and keyboard for communicating via a network
Retargetable	Ben you can explain this one!
Swap partition	a dedicated disk partition that is used as virtual memory
Exporting the display	The process of running an Application on one machine but displaying the interface on another machine.
csh	The C shell. One of the many different types of command lines that are available. Others include the Z shell (zsh), the Bourne again shell (bash) and the Korn shell (ksh)