ed problem

[dinah at krebs.bcm.tmc.edu]

I am having problem with the following script. I want to edit some
c files that begin with AA_. I and to change all combinations of AA_
to the corresponding BB_. I know there is a more efficient way to do
it but the following should work. The problem seems to be that the edit
works successfully, but the file does not get written back with the changes.
It worked for a the first few times (I invoked the script repeatedly until
all occurences were changed. I know it's crude. :-)) Any way the script
prints the changes correctly, but they just don't get written back! Any 
ideas on what is going wrong?

#! /bin/sh
for files in `grep -i AA_ *.c | awk -F: '{ print $1 }' | sort -u`
	do
	ed $files << EOF
/aa_/
s/aa_/bb_/p
/AA_/
s/AA_/BB_/p
/Aa_/
s/Aa_/Bb_/p
w $files
q
EOF
	done
Dinah Anderson					 internet: dinah at bcm.tmc.edu 
Baylor College of Medicine	           uucp: {rutgers,mailrus}!bcm!dinah