When processing text files, the awk language is ideal for handling data extraction, reporting, and data-reformatting jobs. This practical guide serves as both a reference and tutorial for POSIX-standard awk and for the GNU implementation, called gawk. This book is useful for novices and awk experts alike.In this thoroughly revised edition, author and gawk lead developer Arnold Robbins describes the awk language and gawk program in detail, shows you how to use awk and gawk for problem solving, and then dives into specific features of gawk. System administrators, programmers, webmasters, and other power users will find everything they need to know about awk and gawk. You will learn how to:Format text and use regular expressions in awk and gawkProcess data using awk's operators and built-in functionsManage data relationships using associative arraysDefine your own functions'Think in awk' with two full chapters of sample functions and programsTake advantage of gawk's many advanced featuresDebug awk programs with the gawk built-in debuggerExtend gawk by writing new functions in C or C++This book is published under the terms of the GNU Free Documentation License. You have the freedom to copy and modify this GNU manual.Royalties from the sales of this book go to the Free Software Foundation and to the author.