blt-dev software package provides graphics extension library for Tcl/Tk - development files, 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 blt-dev
blt-dev is installed in your system.
Make ensure the blt-dev package were installed using the commands given below,
$ sudo dpkg-query -l | grep blt-dev *
You will get with blt-dev package name, version, architecture and description in a table
| Distro | Ubuntu 16 04 lts xenial xerus |
| Section | Development |
| Package | blt-dev |
| Version | 2.5.3+dfsg-3 |
| Description | graphics extension library for Tcl/Tk - development files |
| Sub Section | Devel |