How do I find files that do not contain a given string pattern?

Question

How do I find out the files in the current directory which do not contain the word foo (using grep)?

Answer 1

You can do it with grep alone (without find).

grep -riL "foo" .

This is the explanation of the parameters used on grep

     -L, --files-without-match
             each file processed.
     -R, -r, --recursive
             Recursively search subdirectories listed.

     -i, --ignore-case
             Perform case insensitive matching.

If you use l (lowercased) you will get the opposite (files with matches)

     -l, --files-with-matches
             Only the names of files containing selected lines are written