Re: [orca-list] orca questions

[Michael Whapples <mwhapples aim com>]

Hello,
Yes unfortunately some of those lock up situations do occur, I don't
know fully why, but could very well exist on other distros. You may wish
to try other distros though, they may perform better, and they might be
better suited if you have some thing specific in mind for what you will
be doing.

Now to explain further about various terms in Linux. Some of this you
might have already found out, but might be interesting.

Linux is the operating system. It manages things like your computer's
hardware, etc, and basically allows the parts inside the metal box be
used. A distribution, its a bit of an odd idea if you are purely used to
windows, is Linux bundled up with various applications, and also
different distributions may have been compiled so as to be optimised for
particular hardware or tasks. The correct distribution is decided by
what you want to do with the system, how you want to interact with the
system and what type of computer you will be running it on. There are
some distributions, ubuntu, debian, and some other main ones are
designed as general purpose distributions, so could be used for a wide
range of tasks. Some others are much more specific and could be unsuited
for tasks other than those they were built for.

The most basic user interface (I say basic as in how it appears, not in
what can be done) is the command line, most distributions (I think all)
have text consoles available where you can work from the command line (a
bit like DOS, but I would say better). The command line features are
provided by the shell, which there are a few of, bash is the most
common, but there is zsh, csh, etc. Each of these shells have there
advantages, and it might come down to personal preference as to which
one to use.

While the text console is very much at the heart of Linux (some,
including me, say that it is where the power of Linux lies), is not the
only user interface. There is a graphical user interface as well (you've
found it already, otherwise how else are you using orca). As I
understand it, various services for graphical user interfaces are
provided by the X server, and specific interfaces are built upon that.
GNOME is one of the graphical user interfaces for Linux, in fact  its a
bit more really than just the user interface, it provides a whole bundle
of graphical applications for using your system. These graphical user
interfaces (such as gnome) are normally referred to as the desktop.
There are other desktops available such as KDE (KDE you might hear of a
bit, its another of the major desktops for Linux).

Now to what GTK is. Its a graphical user interface toolkit. This
basically means that it is a toolkit providing applications an easy way
to produce graphical user interfaces which fit in with a common style.
One feature of GTK is that it provides a way that accessibility
information can be made available from applications to tools such as
orca. GTK is the toolkit used by applications written for the gnome
desktop. There are other graphical user interface toolkits, another main
one is QT, which is used by the KDE desktop.

I said that GTK provides a way for accessibility information to be made
available to orca, it doesn't do it directly, it provides it to at-spi.
At-spi is the accessibility framework used in Linux, and is separated
from GTK because it then can be used by other applications not using
GTK, eg. java applications have information revealed through at-spi when
the java access bridge is installed.

I think that covers the basics. I also hope I got this right, there may
be some small subtle difference as I have done this all from memory
without looking up exact definitions.

Hope it is useful.

Michael Whapples
On Fri, 2008-05-23 at 07:51 -0400, Alex Hall wrote:
> It would lock up when doing things like looking for and 
> installing media codecs for Rhythm Box, not when just moving 
> through menus.  I am quite new to all this: what is GTK? What is 
> Gnome? I think that Gnome is kind of like Dos running behind 
> Windows, but am not sure.  Is GTK like the Windows shell? how 
> hard would it be to put a new "shell" on Ubuntu (or whatever 
> Linux I go with)? Do all Linux versions use GTK, if indeed it is 
> a shell? Thanks again for your help.
>
> Have a great day,
> Alex