Setting a cursor for an undecorated always-on-top window

["Karl H. Beckers" <karl h beckers gmx net>]

Hi there,

I have those 4 undecorated thin GtkDialogs opened from a main app
which form a rectangle.

This rectangle is supposed to stay on top of all other windows, which
works fine if I set the type to GTK_WINDOW_POPUP

Then I want to resize this virtual rectangle by dragging on (or actually
moving) the GtkDialogs. Also, I would like to change the cursor over
the sides of the rectangle.

However, if a GtkDialog is of type GTK_WINDOW_POPUP it doesn't seem
to have a GdkWindow to set the cursor on. If I don't use POPUP, I've
read there's issues with setting the window transient for all.

Can somebody point me to an explanation why GTK_WINDOW_POPUP
can keep windows always on top and other methods can't? If there's
a way to get a GdkWindow from a POPUP dialog?
Or perhaps there's a better way to change the pointer type ... ideally
I'd be looking for some way of changing depending on where in the
window the pointer is.

Doable?
TIA,

Karl.