Hey ,
my logic was to get as many file sin as possible so here is the half part of the code

Please correct me if i am wrong.

grep '^[0-9]\{1,3\}\.[0-9]\{1,3\}\.[0-9]\{1,3\}\.[0-9]\{1,3\}$' followed by respective file names which lies under /var/lib/output/ for me atleast.

Now i want to write the code for reverse dns here .....am i on the right path?

I just wanted to add that i know the commands for reverse dns is Nslookup or dig -x followed by the ip address but the thing how do i make to take the ip address from various files and format it.