Find Files
Find files that contain a text string:
grep -lir "some text" *
The -l switch outputs only the names of files in which the text occurs (instead of each line containing the text), the -i switch ignores the case, and the -r descends into subdirectories. (found here)
Find files from a list of files, like: find all .htaccess files that contain the string ‘RemoveType’:
find -name '.htaccess' | xargs grep -li "RemoveType"
Find all files that don’t contain a certain string:
grep -Lir "some text" *
An uppercase “L” replaces the lowercase one from the example above.