/usr/lib/ruby/1.9.1/tkmngfocus.rb is in libtcltk-ruby1.9.1 1.9.3.0-1ubuntu1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 | #
# tkmngfocus.rb - load tk/mngfocus.rb
#
require 'tk/mngfocus'
|