dir1 = ARGV[0]
dir2 = ARGV[1]
Dir.glob("#{dir1}/*").sort.each do | file |
  filename = File.basename(file)
  puts "#{file} vs #{dir2}/#{filename} :"
  puts `sdiff -bBWs #{file} #{dir2}/#{filename}` #side-by-sideで差分のある行だけを表示
end