Note that pat's search method will be applied to both file names and lines of text. Entering an "a" by itself in the "file pattern" line, and "foo" by itself in the "search pattern" line, will result in guigrep's displaying all the lines containing "foo" in all the files in the current directory whose names contain an "a". But here's the cool part -- the matched lines are displayed in color. Blue is used for the file and line number, red is used for the matched portion of the text, and black is used for the rest of the line.
Note that even should you decide not to pay my registration fee, you are permitted by the terms of my copyright to keep package pat installed and use applications written by licensed users (or me). You are only expected to pay if you wish to use package pat for development of software. Thus, you can keep and use guigrep.
Future versions of guigrep will, hopefully, become more useful and sophisticated. Hope you like it.