Find all files matching 'name' on linux system, and search with them for 'text'

Question

I need to find all instances of \'filename.ext\' on a linux system and see which ones contain the text \'lookingfor\'.

Is there a set of linux command line operation

Answer 1

I find the following command the simplest way:

grep -R --include="filename.ext" lookingfor

or add -i to search case insensitive:

grep -i -R --include="filename.ext" lookingfor