Render GitHub Flavored markdown to temp file and view it

gfm_file.rb

#!/usr/bin/env ruby
exit unless ARGV.length > 0

require 'github/markdown'
require 'tempfile'
t=Tempfile.new('gfm_foo')
t.write(GitHub::Markdown.render_gfm(File.read(ARGV[0])))
t.rewind()
exec("/etc/alternatives/x-www-browser #{t.path}")
t.close()