I use the grep command on Unix for a long time already. Nevertheless I found out that I missed something it can do.
Maybe I never looked hard enough, maybe I never really needed this: Looking for files which do not contain a certain string.
Listing all files which contain a given string is easy. For example looking for all files in the current directory containing the word "computer" would be:
grep -li computer *
The -v switch does not help when looking for files not containg a string. Instead the -L switch has to be used:
grep -iL computer *