The GTK+ module is designed to be loaded using gnome-settings-daemon by the
gnome-packagekit package.
It can however be launched for testing using:
GTK_MODULES="$GTK_MODULES:/usr/lib/gtk-2.0/modules/pk-gtk-module.so" application
The module installs a custom default pangocairo font map during gtk_init().
Pango will then call back with any languages which need installing, and these
are queued up. In an idle callback these are emitted as an asyncronous D-BUS
method to the session PackageKit InstallFonts() method.
If configured to do so, this will prompt the user to install new fonts.
PackageKit is a system designed to make installing and updating software on
your computer easier. The primary design goal is to unify all the software
graphical tools used in different distributions, and use some of the latest
technology like PolicyKit to make the process suck less.
The actual nuts-and-bolts distro tool (yum, apt, conary, etc) is used by
PackageKit using compiled and scripted helpers. PackageKit isn't meant to
replace these tools, instead providing a common set of abstractions that can
be used by standard GUI and text mode package managers.
PackageKit itself is a system activated daemon called packagekitd. Being
system activated means that it's only being run when the user is using a text
mode or graphical tool, and quits when it's no longer being used. This means
we don't delay the boot sequence or session startup and don't consume memory
when not being used.
