application cache update

[Matej Križan]

Binary package hint: desktop-file-utils

Related packages: gnome-panel 1:2.30.0-0ubuntu2, python-gmenu 2.30.0-0ubuntu4, xdg-utils 1.0.2-6.1ubuntu3

The /usr/share/applications/desktop.*.cache file is not updated when an (attached example) entry is added by xdg-desktop-menu or desktop-file-install. Gnome-panel detects creation of a new desktop file in /usr/share/applications and displays it in the menu immediately, but on its next start (e.g. after logout/login) the old menu without new entry is displayed because of the cache. This is not a problem for native deb packages, for which dpkg triggers the python-gmenu postinst script responsible for updating the cache. This is only a problem for ISVs, that install their (LSB) packages themselves. This bug will force them to delete all such cache files. Is this deletion acceptable?

Another possible solution would be to update the cache in update-desktop-database command.

I haven't found such cache on Debian testing nor Fedora 13, so I think this is Ubuntu's invention, thus reporting it here.

ProblemType: Bug
DistroRelease: Ubuntu 10.04
Package: desktop-file-utils 0.16-0ubuntu2
ProcVersionSignature: Ubuntu 2.6.32-22.36-generic 2.6.32.11+drm33.2
Uname: Linux 2.6.32-22-generic x86_64
Architecture: amd64
Date: Fri Jun 11 15:32:54 2010
InstallationMedia: Ubuntu 10.04 LTS "Lucid Lynx" - Release amd64 (20100429)
ProcEnviron:
 LANG=en_US.utf8
 SHELL=/bin/bash
SourcePackage: desktop-file-utils

[Sebastien Bacher (seb128)]

thank you for your bug report, whatever code is installing a system desktop entry should update the cache, that's not really a bug in the cache code or desktop-file-utils if the installater is buggy

[Matej Križan (krizan)]

Well, I don't think the custom package installer should be responsible for knowing about, detecting and updating all such caches for all possible Linux distributions. That's why LSB and freedesktop try to unify (and simplify) all common tasks, desktop menu installation in this case. If your distro improves something it should do that "under the hood", keeping the proposed interfaces working, xdg-desktop-menu/desktop-file-install in this case.

[Sebastien Bacher (seb128)]

right, that's why the bug is still open as a wishlist

[Michael Terry (mterry)]

Deleting the cache files is 'safe', just slightly reduces performance until a package is updated and forces a regeneration. Perhaps a really easy short term fix is just have desktop-file-install blow away the cache when it installs a file.

Note that this bug is Ubuntu-specific and arises because of gnome-menus with its 22_desktop-cache.patch and dpkg trigger that regenerates the cache when a desktop file is changed.

[Felix Kuehling (felix-kuehling)]

This bug will affect all users installing fglrx on Ubuntu 10.10 using the Catalyst installer. CCC-LE menu entries will be missing in the System/Preferences menu until we have implemented a workaround in our installer.