What has not been commented on in the follow-ups to shlomif's post, is the (absoloutely correct) point that the explanations given for the flags used with grep are erroneous and misleading. This is especially serious in a book aimed at people who are not veryexperienced with Linux.

I am surprised not only that it slipped past the proofreaders but that O'Reilly have this on their website to promote the book. I had been thinking of getting it, but seeing such a sloppy error has made me reconsider.