https://blog.offline-net.com/2012/05/01/ubuntu-12-04%ef%bc%9agnome-terminal%e3%80%8e%e2%97%8b%e2%96%b3%e2%97%87%e3%80%8f%e3%82%92%e6%ad%a3%e3%81%97%e3%81%8f%e8%a1%a8%e7%a4%ba%e3%81%99%e3%82%8b/