There are a few "system" things that need updating after some GARstow packages have been installed: the GNU info directory file, ldconfig's symlinks (although these really should be done in the individual directory), scrollkeeper catalogues, and so on. GARstow should check to see if they need updating, and do so if necessary. The generated files could be written straight into the stow dir, or could live in a "garstow_system" package, or something like that.