Tk now available for Rexx too — Preceding unsigned comment added by 18.104.22.168 (talk) 01:35, 2 April 2014 (UTC)
I have not found any hint that xforms is cross-platform:
XForms is a graphical user interface toolkit for X based on the X11 Xlib library.
Rainglasz (talk) 09:30, 26 April 2016 (UTC)
Lacking a reliable source, zenity appears to be a standalone application (no widget library). Where a library would be, zenity uses Gtk (making it not topical here) TEDickey (talk) 19:38, 29 May 2017 (UTC)