However, it does use a simple but clever indexing approach that considerably reduces the amount of work to be done by the program on each search. If you have a very large site with many users searching constantly, you might not want to use it. We cannot tell you how to install CGI programs on your web server. Don't send us email about it. After you download the source code, you need to edit it to suit your site.
Mandatory settings are at the top.
Change the filenames as appropriate. Run search-index on a regular basis, preferably from cron or another automation facility. For a list of arguments, run search-index without specifying any arguments.