hiding windows when pressing on window manager (X)

[Neil Zanella <nzanella gmail com>]

Hello,

I would like to know, is there a way to tell GTK that when the user
clicks on the
window manager's (X) usually found in the upper right hand corner of window
frames, the window is to be hidden instead of destroyed? This behavior is
the one needed for child windows of parent windows which the main
application usually just hides.

Thanks,

Neil