For people who create and modify text files, "sed" and "awk" are power tools for editing. Most of the things that you can do with these programs can be done interactively with a text editor. However, using "sed" and "awk" can save many hours of repetitive work in achieving the same result.To master "sed" and "awk" you must thoroughly understand UNIX regular expressions, and understand the syntax of "sed" and "awk" commands. This handbook treats regular expressions as a foundation for learning about"sed" and "awk" and contains a comprehensive treatment of "sed" and "awk" syntax. It emphasizes the kinds of practical problems that "sed" and "awk" can help users to solve, with many useful example scripts and programs.Contents include: A tutorial showing basic operations of "sed" and "awk"Regular expression syntax and examplesBasic and advanced "sed" commandsFeatures of "awk" (plus "gawk" and "nawk")Common programming constructsAdvanced topicsUser-contributed scripts