How to find and replace all occurrences of a string recursively in a directory tree?

Question

Using just grep and sed, how do I replace all occurrences of:

a.example.com

with

b.example.com

within a

Answer 1

I know this is a really old question, but...

1. @vehomzzz's answer uses find and xargs when the questions says explicitly grep and sed only.

2. @EmployedRussian and @BrooksMoses tried to say it was a dup of awk and sed, but it's not - again, the question explicitly says grep and sed only.

So here is my solution, assuming you are using Bash as your shell:

OLDIFS=$IFS
IFS=$'\n'
for f in `grep -rl a.example.com .` # Use -irl instead of -rl for case insensitive search
do
    sed -i 's/a\.example\.com/b.example.com/g' $f # Use /gi instead of /g for case insensitive search
done
IFS=$OLDIFS

If you are using a different shell, such as Unix SHell, let me know and I will try to find a syntax adjustment.

P.S.: Here's a one-liner:

OLDIFS=$IFS;IFS=$'\n';for f in `grep -rl a.example.com .`;do sed -i 's/a\.example\.com/b.example.com/g' $f;done;IFS=$OLDIFS

Sources:

• Bash: Iterating over lines in a variable

• grep(1) - Linux man page

• Official Grep Manual

• sed(1) - Linux man page

• Official sed Manual

Answer 2

For me works the next command:

find /path/to/dir -name "file.txt" | xargs sed -i 's/string_to_replace/new_string/g'

if string contains slash 'path/to/dir' it can be replace with another character to separate, like '@' instead '/'.

For example: 's@string/to/replace@new/string@g'