Persisting driver configuration

[Eirik Byrkjeflot Anonsen]

Christoph Brill <egore at gmx.de> writes:

> Hi list,
>
[...]
> Why am I asking this question? Because of our friend
> xf86-input-synaptics. This driver has the ability to change it's options
> at runtime by putting them into a shared memory. These changes, of
> course, are not persisted in the xorg.conf. And this, of course, is
> annoying to the user.

At the same time, of course, it would be far more annoying if all
changes had been automagically persistent.  Since it is typically
necessary to fiddle with various settings for a while to figure out
exactly which changes are good, it is extremely important to be easy
to revert to the previous starting point.  And it is extremely
important that you know that you can revert to the current position.

As long as no settings are persistent unless the user has explicitly
modified a configuration file, this is trivial.  Just make sure to
make a backup of any file you change.  As soon as the system starts
changing persistent settings by itself, this gets impossible.  In
particular, it makes it impossible to be confident that you can revert
to where you were.

eirik