How to get the X display variable?

[Erik Mouw <J A K Mouw its tudelft nl>]

I have a GTK application in which I want to iconify a window that's not
owned by that particular application. I figured out that I need
XIconifyWindow() or XWithDrawWindow() for that. Both functions need the
same parameters: Display *display, Window w, int screen_number. I can
figure out the Window parameter, but how do I get the display and
screen_number parameters from GTK/GDK structures?


Erik

-- 
J.A.K. (Erik) Mouw, Information and Communication Theory Group, Department
of Electrical Engineering, Faculty of Information Technology and Systems,
Delft University of Technology, PO BOX 5031,  2600 GA Delft, The Netherlands
Phone: +31-15-2785859  Fax: +31-15-2781843  Email J.A.K.Mouw@its.tudelft.nl
WWW: http://www-ict.its.tudelft.nl/~erik/