Building a Point of Sale or (How does X work?)

[Karl F. Larsen]

Valter Nogueira wrote:
> Today I went to the supermakert and while wainting in line, the
> point-of-sale frozen.It died.
> 
> Well, it could be disturbing for most people - but I saw the operator
> rebooting software and it was Linux. I could not realize the distro and I
> can say that it loads tons of services during start-up (more than I am used
> to see)

	Ubuntu can and I expect does do the same thing. You don't 
need to know a lot about X windows, but you need to know how 
to use it.


> 
> After booting, with no login nor any kind of visible window manager,
> appeared the graphical user interface of POS and continued from the last
> product registered.
> 

	The local Unix connected to the Server for the store. This is 
pretty easy to do. You use System - Preference - startup 
programs and perhaps Keyboard Shortcuts. It takes time to set 
up and that is what the store IT people do.

> OK. It is a long, long history. Well, what I want to know is what is the
> best way to produce a effect like that in my distro of choice (Ubuntu)?
> 
> Tons of options suddenly crossed my mind. A Gnome/GTK program using
> full-screen started at gnome starting. A Java/Swing Application, a xfce
> application (if such thing exists) and suddenly I figured out that I don't
> have a clear idea of how X works at all.
> 
> In Win32 that is just one way to do anything: Win API and Petzold way.
> Anything else (including .NET) are just layers between app and gdi/kernel.
> 
> So, what is the learning path to programming X? Could anyone send me a
> direction?
> 
> Thanks
> 
> Valter
> 
> 	You do not need to know much at all about X windows. Learn to use Ubuntu.


73 Karl



-- 

	Karl F. Larsen, AKA K5DI
	Linux User
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