Searching & Replacing string in a File

[Sanjay Verma]

Hi Friends,
I've hundreds of file in one directory and want to create a script which searches for a specific string "AB-00" and replace with "AB-11". Any suggestions? -Sanjay

[Bhuvaneswari Selvaraj]

for i in `ls`
do
rm ./sed_file 2>/dev/null
sed 's/AB-11/AB-11/' $i > ./sed_file
mv ./sed_file $i
done

this script will do... sed_file is a temp file. When you run this script ensure that it does not exist in your current dir

[Bhuvaneswari Selvaraj · Accepted solution]

Sorry, I made a mistake while copying the script from my test machine to your reply..

The script must be like as shown in this..

for i in `ls dirname`
do
rm ./sed_file 2>/dev/null
sed 's/AB-00/AB-11/' $i > ./sed_file
mv ./sed_file $i
done

and make sure that the script itself is not in the ls output (save it a different location)

[Bhuvaneswari Selvaraj]

If it does not work, give the sed command in double quotes like

sed "s/$var1/$var2/" file1

[Sanjay Verma]

Hi Bhuvaneswari,
Thanks for your reply. Some concerns are:
a) Why not put the script in the same directory?
b) What 'dirname' refers to?
c) Why it's required to create the temp file?? - Sanjay

[Sanjay Verma]

Still having the issues like
- unable to run from other directory
- when run from the same directory it's changing the permission in the script too.
Can you suggest the way to correctly run this from other dir??

[V.Tamilvanan]

Hi,
Run this below script in your direcory where all your files need to be modified.

#!/usr/bin/ksh
for file in *
do
cp $file $file.bak
sed 's/AB-00/AB-11/g' $file.bak >$file
rm $file.bak
done

[V.Tamilvanan]

Hi,
Make sure you r not copying the script to the directory as it will change the scripts itself.
You just run those commands don't copy as a file.

[Sanjay Verma]

Thanks Tamil. What about running these commands from a script from another dir??

[Sanjay Verma]

It'll be great if I can run this script from another dir since it's changing the file continuously.

[Bhuvaneswari Selvaraj]

Hi,

Let me start from the beginning.. Assume that the files you want to change are in dir /temp/mydir

Copy the script that I had sent to you to /temp
Change the script, I mean the first line, ls dirname to ls /temp/mydir and execute the script.

Why it shud not be in the same dir is because, even your script will also get changed if it is in the same dir. hope this helps...

[V.Tamilvanan]

Yes. You can run this script from any directory.
You need to modify the scripts file search path with absolute path.
Suppose your files need to be modified are in a directory called /home/data. Then the script should be

#!/usr/bin/ksh
for file in /home/data/*
do
cp $file $file.bak
sed 's/AB-00/AB-11/g' $file.bak >$file
rm $file.bak
done


I hope this addressed all your concerns

[Sanjay Verma]

Dear Bhuvaneswari & Tamil,
It all worked perfectly fine. What I did also is changed the script to .name and all ok now. Thanks & appreciate for you support & quick response.