How to control programs run at startup?

KDE provides a wonderful tool in systemsettings ("Startup and Shutdown" -> "Autostart") for managing your personal autostart services (in either of the .kde directories) however it doesn't cover systemwide autostart scripts provided by your distribution packages, or created by the gnome apps.

Sometimes however it can be useful to override your distribution autostart preferences, for example I don't like having the printer-applet running as I don't own a printer, but it seems a shame to uninstall it in case I need it.

The correct way to disable a package installed is actually to copy it to your personal autostart folder. Anything of the same name in ~/.kde/share/autostart and/or /usr/share/autostart/ (also can be ~/.kde4/Autostart) overrides the .desktop file in the default installations. Once we have copied the .desktop file we can make changes. Add the following line to the .desktop file you have just copied:

Hidden=true 

KDE also restores your session when you log in, so if psensor is running when you log out, it will be started up again when you log in. To change that, just close psensor (i.e. actually quit the program, don't just close the window). If psensor is not running when you log out, it should not start up again when you log back in.

I found this useful, taken from David Edmundson's blog:

~/.kde/Autostart
~/.kde/share/autostart
~/.config/autostart
~/.local/share/autostart
/etc/xdg/autostart
/usr/share/autostart

I don't really know why we have so many... Anything inside the /usr/ or /etc folder will have been installed by your distribution.