Question

it seems that Ruby GTK apps are unable to run in nongraphical environment.. while python apps are able to.

oversimplified examples (even without the gtk main loop), demonstrating this behavior:

gtktest.py:

#! /usr/bin/python
import gtk
print('the end')

gtktest.rb:

#! /usr/bin/ruby
require "gtk2"
puts('the end')

X window environment:

$ ./gtktest.py
the end
$ ./gtktest.rb
the end

non X environment:

$ ./gtktest.py
/usr/lib/pymodules/python2.5/gtk-2.0/gtk/__init__.py:57: GtkWarning: could not open display
  warnings.warn(str(e), _gtk.Warning)
the end

$ ./gtktest.rb
/usr/lib/ruby/1.8/gtk2.rb:12:in `init': Cannot open display:   (Gtk::InitError)
    from /usr/lib/ruby/1.8/gtk2.rb:12
    from ./gtktest.rb:2:in `require'
    from ./gtktest.rb:2

as you can see, python version runs succesfully with a warning, ruby one fails immediately
on gtk importing
(python one works even with a gtk main loop, with VTE terminal doing some text processing)

is someone aware of a possibility do have those ruby gtk apps running in non-X ?

environment: debian squeeze, python-gtk2, libgtk2-ruby

Answer 1

Yes you can, setup Xvfb.