grep -r --include=<pattern> <string> <directory> grep -r --include=*.nk "Shot200" . The above code will search any .nk files that contain the word 'Shot200' in the current folder and its subfolders recursively .
or use 'find'
find . -name "*.nk" -exec grep "Shot200" {} +
or
find . -name "*.nk" | xargs grep "Shot200"
