These are some window manager related functions for use by client
programs, as per the "Inter-Client Communication Conventions Manual"
and some of the Net-WM "Extended Window Manager Hints".
Note: normally, SlackBuilds that build perl modules include the
"make test" command. Here, it's disabled by default, as it will
cause the build to fail if there is no X server running (or if X's
DISPLAY variable isn't set). If you want to enable the tests, export
MAKETEST=yes in the script's environment. Note that the test will
leave your desktop with a solid black background (replacing whatever
wallpaper you might have had).