I need to recursively search for a specified string within all files and subdirectories within a directory and replace this string with another string.
I know that the command to find it might look like this:
grep 'string_to_find' -r ./*
But how can I replace every instance of string_to_find with another string?
10 Answers
Another option is to use find and then pass it through sed.
find /path/to/files -type f -exec sed -i 's/oldstring/new string/g' {} \;
I got the answer.
grep -rl matchstring somedir/ | xargs sed -i 's/string1/string2/g'
You could even do it like this:
Example
grep -rl 'windows' ./ | xargs sed -i 's/windows/linux/g'
This will search for the string 'windows' in all files relative to the current directory and replace 'windows' with 'linux' for each occurrence of the string in each file.
This works best for me on OS X:
grep -r -l 'searchtext' . | sort | uniq | xargs perl -e "s/matchtext/replacetext/" -pi
Source:
Usually not with grep, but rather with sed -i 's/string_to_find/another_string/g' or perl -i.bak -pe 's/string_to_find/another_string/g'.
Other solutions mix regex syntaxes. To use perl/PCRE patterns for both search and replace, and process only matching files, this works quite well:
grep -rlIZPi 'match1' | xargs -0r perl -pi -e 's/match2/replace/gi;'
match1 and match2 are usually identical but match2 can contain more advanced features that are only relevant to the substitution, e.g. capturing groups.
Translation: grep recursively and list matching filenames, each separated by null to protect any special characters; pipe any filenames to xargs which is expecting a null-separated list; if any filenames are received, pass them to perl to perform the actual substitutions.
For case-sensitive matching, drop the i flag from grep and the i pattern modifier from the s/// expression, but not the i flag from perl itself. To include binary files, remove the I flag from grep.
Be very careful when using find and sed in a git repo! If you don't exclude the binary files you can end up with this error:
error: bad index file sha1 signature
fatal: index file corrupt
To solve this error you need to revert the sed by replacing your new_string with your old_string. This will revert your replaced strings, so you will be back to the beginning of the problem.
The correct way to search for a string and replace it is to skip find and use grep instead in order to ignore the binary files:
sed -ri -e "s/old_string/new_string/g" $(grep -Elr --binary-files=without-match "old_string" "/files_dir")
Credits for @hobs
Here is what I would do:
find /path/to/dir -type f -iname "*filename*" -print0 | xargs -0 sed -i '/searchstring/s/old/new/g'
this will look for all files containing filename in the file's name under the /path/to/dir, than for every file found, search for the line with searchstring and replace old with new.
Though if you want to omit looking for a specific file with a filename string in the file's name, than simply do:
find /path/to/dir -type f -print0 | xargs -0 sed -i '/searchstring/s/old/new/g'
This will do the same thing above, but to all files found under /path/to/dir.