libidn11-dev software package provides Development files for GNU Libidn, an IDN library, 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 libidn11-dev
libidn11-dev is installed in your system.
Make ensure the libidn11-dev package were installed using the commands given below,
$ sudo dpkg-query -l | grep libidn11-dev *
You will get with libidn11-dev package name, version, architecture and description in a table
| Distro | Ubuntu 16 04 lts xenial xerus |
| Section | Library development |
| Package | libidn11-dev |
| Version | 1.32-3ubuntu1.1 [amd64, i386], |
| Description | Development files for GNU Libidn, an IDN library |
| Sub Section | Devel |