I remember (probably around 10 years ago) of a compromised server with a couple of strange files ". " and ".. ". After looking into it I realized that they were

I remember (probably around 10 years ago) of a compromised server with a couple of strange files ". " and ".. ". After looking into it I realized that they were a ftp server and a process name changer. I would say your guess is correct, this script is probably used to spot weird file names which would pass unnoticed with a simple "ls".