From the FAQ:

> Subject: 164) How do I tell if a scrolled window's scrollbars are visible?
> Answer: Use XtGetValues() to get the scrollbar widget ID's, then use
> XtIsManaged() to see if they are managed (visible).

Apparently, this is no longer true with Motif 2.1. What happens (after
some poking around with editres; I avoid looking into the OpenMotif
sources because of licensing issues) is that the scrollbars, when not
used, are simply pushed off the parent's [Scolled]Window boundaries.
Then, it appears, one has to get the coordinates of the bar's rectangle
and check whether it lies within that of the scrolled window or not. Am
I missing a more elegant solution?