Writing Touchscreen calibration utility

[Sergei Mutovkin]

Hello everyone,

I'm new to the X development and this is my first ever post to this ML...

I have a task of writing graphical touchscreen calibration utility for
the ELOTouch Serial controller ( for elographics Xorg driver). I have
already written ncurses based version for console (for initial
calibration) and now need graphical one that will be running under
XOrg. I have several questions to which I was unable to find answers
so far:

1. Is there any way to stop touchscreen (elographics) driver while X
is running, then do my calibration (reading info from ttyS). After
that saving new configuration to xorg.conf and starting driver again
with new ( I guess reparsed) xorg.conf.

2. What library is used by the rest of the software to modify
xorg.conf and make sure that it is always in consistent state? (for my
command line calibration I just used my own small "parser", but might
be a better way).

3. Where can I find (if it even exists) up to date documentation on
what is available (in terms of APIs) in Xorg source code [which is for
me still a HUGE chunk of code, just to be able to go through it].

4. Is there any reason not to use Qt for this utility, but to use Xlib instead?

Thank you very much in advance,
Sergei