I have the script which appends month and year to the name of the
file. Now every time when I append the month-year combination I
have to subtract 2 months from the current date and then append
it, since we are sending our vendor 2 months prior worth of data
eveytime.

#! /usr/bin/ksh

filefullname=$1
filename=${filefullname%.*}
fileext=${filefullname##*.}

DATE=`date +%m%y`

newfilename="${filename}${DATE}.${fileext}"

mv $filefullname $newfilename

I am not sure how to go about it, Any help or sample script would help me get going...

Thanks..