I am using Ubuntu 14.04 LTS. I want to know some extra security tips in dealing with PDF files. I found that we can easily make a PDF file password protected using
pdftk command from here.
But is it possible to make PDF files to expire after a specific date?
I mean a PDF displayable only for a particular period of time and after that if someone tries to open it he would get only a message like "Sorry, nothing to display".
Is there any command or script for that?