$ sudo apt-get update
$ sudo apt-get install libio-string-perl 

libio-string-perl is installed in your system.

Make ensure the libio-string-perl package were installed using the commands given below,

$ sudo dpkg-query -l | grep libio-string-perl *

You will get with libio-string-perl package name, version, architecture and description in a table

libio-string-perl package basic information: