[Mageia-dev] Proposal: Updating released versions (long post)

Thu Oct 14 10:44:39 CEST 2010

On Saturday, 9 October 2010 10:10:36 Renaud MICHEL wrote:
+> On samedi 09 octobre 2010 at 05:45, andré wrote :
+> > Note that configuration files that have been changed from the
+> > installation default are often already saved.  (Generally ".old" is
+> > appended to the configuration file name, sometimes ".new" to the new
+> > configuration file.)
+> 
+> But here you are only talking about system-wide configuration files, which
+> are known of rpm as they are part of the package and marked as config
+> files. But what about user specific configuration files?
+> For the easy kind, where a program will have a single configuration file
+> (or dedicated directory), a pre-inst script could find it in the home of
+> each users and backup them. But you have cases of programs which have
+> configuration scattered in multiple shared directories (like KDE), or even
+> non-deterministic configuration files and it can become very tricky to find
+> all the files to backup.
+
+A snapshot-based solution (e.g. on btrfs) would mean you don't have to "find 
+all the files".
+
+> And you have the really hard kind, where the same configuration file may be
+> shared by different packages. For example, plasma applet configurations are
+> stored in a few ~/.kde4/share/config/plasma* files.
+
+Well, now the problem is to snapshot multiple filesystems. I am not sure if 
+this is easy with btrfs and subvolumes.
+
+But, IMHO, the software in question should ideally be able to handle upgrade 
+*and* downgrade, otherwise environments with shared home directories would 
+have to be *very* careful about keeping *all* software on *all* machines 
+exactly in step.
+
+Regards,
+Buchan
+