c-sig software package provides signature tool for GNU Emacs, you can install in your Ubuntu 16.04 LTS (Xenial Xerus) by running the commands given below on the terminal,
$ sudo apt-get update $ sudo apt-get install c-sig
c-sig is installed in your system.
Make ensure the c-sig package were installed using the commands given below,
$ sudo dpkg-query -l | grep c-sig *
You will get with c-sig package name, version, architecture and description in a table
| Distro | Ubuntu 16 04 lts xenial xerus |
| Section | |
| Package | c-sig |
| Version | 3.8-20 |
| Description | signature tool for GNU Emacs |
| Sub Section |