Re: [CentOS] Log File Reviewing

So gawk does all that sed does and more? I suppose I can start with

Can't really answer that. In 15 years of using UNIX systems, I've never touched sed. :)

With Gawk's BEGIN and END blocks you can use it to write full programs, which is kind of nice.

that in this case, I always wanted a book on regexe's so I think I am going to order O'Reilly's Mastering Regular Expressions, Third Edition. They also have a sed & awk, Second Edition book, but its 10+ years old, does that matter, has sed/awk changed any since then?

The link I sent you is the 3rd edition of that book. Dated 2004. The book (Effective AWK Programming) is available completely free, but is also available in dead-tree editions. I printed and bound my PDF and saved a few dollars.