by
a <B>__SWM_ROOT</B> or <B>__WM_ROOT</B> property placed on the top-level
window by the window manager.
If <I>tkwin</I> is not associated with a virtual root (e.g.
because the window manager does not use virtual roots) then *<I>xPtr</I> and
*<I>yPtr</I> will be set to 0 and *<I>widthPtr</I> and *<I>heightPtr</I>
will be set to the dimensions of the screen containing <I>tkwin</I>.
<H3><A NAME="M6">KEYWORDS</A></H3>
<A href="../Keywords/G.html#geometry">geometry</A>, <A href="../Keywords/H.html#height">heig