$ sudo apt-get update
$ sudo apt-get install libcos4-1 

libcos4-1 is installed in your system.

Make ensure the libcos4-1 package were installed using the commands given below,

$ sudo dpkg-query -l | grep libcos4-1 *

You will get with libcos4-1 package name, version, architecture and description in a table

libcos4-1 package basic information: