Swish++ is a Unix-based file indexing and searching engine, which is extremely fast in doing it’s job. Swish++ consists of two parts. Index++ can index wll your files with this command: index++ -e “text:*.txt” . (dot at the end required).
Search++ will simply search for a string you mentioned in the search with staistics of it’s occurance in searched files, ie, search++ test
For more information go to their website: http://swishplusplus.sourceforge.net/