mime types and related application is a pain with linux. Since freedesktop (http://www.freedesktop.org), thinks seems to be better. However, independent mime management still exists in Ubuntu : For instance, promoted programs like Firefox (https://bugzilla.ubuntu.com/show_bug.cgi?id=7023), uses a configuration different from gnome.

What is the current state ?

2 packages coexist that manage mime types:

  • mime-support
    • provides /usr/sbin/update-mime
    • handle /etc/mailcap and /etc/mime.types
    • I think it's used by firefox
  • shared-mime-info
    • provides /usr/bin/update-mime-database
    • handle freedesktop specification
    • Used by gnome

What to do ?

  • Find programs that use mime-support and force them to use shared-mime-info.
  • Suppress mime-support and make shared-mime-info handle /etc/mailcap and /etc/mime.types for compatibility.



  • /etc/mail.type store relation between file extensions and mimetypes. Lines use the form: typemime extensions
  • /etc/mailcap and $HOME/.mailcap store relation between mimetypes and program that handle them. Lines use the form: mimetype ; application %s.

See update-mime(8) and RFC 1524 for details


  • why is there mime type without extension?
  • freedesktop mime specification are-they enough to build /etc/mailcap?

To Do

  • search wich software use /etc/mailcap and /etc/mime.type
  • tweak /usr/bin/update-mime-database in order to build /etc/mime.type
    • Infos already exists in /usr/share/mime/globs and /usr/local/share/mime/globs
  • Changing a "preferred application" in Gnome should change the application launched for at least the main mime type


MataroSessionsWorkshops/MimeManagement (last edited 2008-08-06 16:29:18 by localhost)