If graphics = TRUE
and a windowing system is available
(Windows, macOS or X11 via Tcl/Tk) a listbox widget is
used, otherwise a text menu. It is an error to use menu
in a
non-interactive session.
Ten or fewer items will be displayed in a single column, more in
multiple columns if possible within the current display width.
No title is displayed if title
is NULL
or ""
.