I have a bit of data on the window managers on my own (Red Hat) system.  There are three window managers available:  Gnome, KDE, and "failsafe".

"Failsafe" seems to be an extremely minimalist windowing system.  It brings up windows without any decorations, and when I ask for something at position (20,20) I get the drawable area at (20,20).  This is what "glutGet" returns as well.  With no decorations, there really isn't any alternative.

KDE and Gnome both behave in a similar fashion.  When I ask for a window at position (20,20), I get a window whose outside decorations start at (20,20) and whose drawable area starts at (26,40).  When I call "glutGet" to ask for the window position I get (26,40).

KDE and Gnome differ in the size of the initial window.  I asked for a window of 30x30 pixels.  Gnome gave me what I asked for; KDE gave me a window 78 pixels wide and 30 pixels high.  This was the case for three different windows, with three different titles.  I find that the width for KDE is 78 pixels if I vary the height and desired width as well.  Gnome gave me the desired size every time.

I have a fourth entry in the Window Manager list called "Default."  It looks and behaves just like KDE, so it probably is.

What happens with other people's systems?

John F. Fay
john.fay@eglin.af.mil

"It is a poverty to decide that an unborn child must die in order that you may live as you like."  - Mother Teresa