[sane-devel] As instructed by /etc/udev/rules.d/libsane.rules

[Julien BLACHE]

Alesh Slovak <alesh.slovak at avasys.jp> wrote:

Hi,

> Ah, good point. But the rules will need to be regenerated when a SANE
> upgrade contains changes to the generation tool, which means the third
> party .desc files from which the rules are generated need to be
> someplace where SANE can find them. We could use an environment
> variable for this.

If we really want to do that, then we must agree on a location for those
files and we need to ship a wrapper script that will rebuild the rules
from the desc files.

This is how it'll work:
 - third party backend package is installed
    -> calls update-sane-udev <descname without .desc>
       -> /lib/udev/rules.d/XX_backendname.rules is created
 - sane-backends is upgraded
    -> calls update-sane-udev
       -> all rules files are recreated

Rules files lie in /lib nowadays so they are not conffiles
anymore. Users can override a particular rules file by copying it to
/etc/udev/rules.d and making their changes. The files in /etc take
precedence over the files in /lib.

Will only work with recent enough udev and distros, would work on Debian
starting with Squeeze.

JB.

-- 
Julien BLACHE                                   <http://www.jblache.org> 
<jb at jblache.org>                                  GPG KeyID 0xF5D65169