How to get the mouse cursor position in TK?

[Heiner Litz]

HI

i have got a listbox widget. I want to select one line and then push the
right mouse button to pull up a menu.

I need the mouse position in pixels so I know where to position the menu
widget and I need to know in what line the right mouse button was pressed,
because the menu depends on the context of the selected text in the listbox.

thx a lot!