Linux: Find text in a large number of files

If you need to find a string in a file, you would typically use:

grep -H "string to find" filename.ext

However, grep doesn’t handle a large number of files well. If you specify

grep "string" *

or even

<em>grep "string" `find ./`</em>

you may find yourself facing this error:

bash: /bin/grep: Argument list too long

If you need to search for a string in a lot of files then you can use a simple bash script to do the searching for you.

In this sample, I am looking for a string “sample string” in a directory named “./sample/”:

for i in `find ./sample/`; do grep -H "sample string" $i; done

This uses the find command to do the searching. It actually returns a list of filenames, which we can then grep one-by-one. The -H option tells grep to let us know the filename it found the string in so we can go right into that file to find the location of it.