libykclient3 software package provides Yubikey client library runtime, you can install in your Ubuntu 14.04 LTS (Trusty Tahr) by running the commands given below on the terminal,
$ sudo apt-get update $ sudo apt-get install libykclient3
libykclient3 is installed in your system.
Make ensure the libykclient3 package were installed using the commands given below,
$ sudo dpkg-query -l | grep libykclient3 *
You will get with libykclient3 package name, version, architecture and description in a table
| Distro | Ubuntu 14 04 lts trusty tahr |
| Section | Libraries |
| Package | libykclient3 |
| Version | 2.12-1 |
| Description | Yubikey client library runtime |
| Sub Section | libs |