Tidak dapat menemukan paket libffi dan libffi5-dev di Ubuntu 12.04.4 melalui apt-get
$ sudo apt-get install libffi libffi5-dev Reading package lists... Done Building dependency tree Reading state information... Done E: Unable to locate package libffi E: Unable to locate package libffi5-dev percobaan lain: $ sudo apt-get install libffi5 libffi-dev Reading package lists... Done Building dependency tree Reading state information... Done E: Unable …