How can I use grep to find a word inside a folder?

Question

In Windows, I would have done a search for finding a word inside a folder. Similarly, I want to know if a specific word occurs inside a directory containing many sub-directo

Answer 1

grep -nr search_string search_dir

will do a RECURSIVE (meaning the directory and all it's sub-directories) search for the search_string. (as correctly answered by usta).

The reason you were not getting any anwers with your friend's suggestion of:

grep -nr string

is because no directory was specified. If you are in the directory that you want to do the search in, you have to do the following:

grep -nr string .

It is important to include the '.' character, as this tells grep to search THIS directory.