hey all,

I have files in the format of
ABCD20061101
and
ABCDEF20061101
in one directory, I would like to change all ABCD20061101 to ABCDEF20061101 and the problem is if I do a simple pattern match of ABCD, then those ABCDEF20061101 would also change to ABCDEFEF20061101, can anybody help? thanks!

#!/bin/ksh
find /path/to/files -name *20061101 | \
while read file 
do
   newfile=${file%%20061101}
   newfile=$newfile"EF"20061101
   mv "$file" "$newfile"
done

Sorry that I wasn't clear enough, the filename could be

ABCD20061101.txt or ABCD12345678.txt

and I want them to change to

ABCDEF20061101.txt or ABCDEF12345678.txt

Please help! Thanks!