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This book teaches you about the language and how you can use it effectively. You should already be familiar with basic system commands, such as and, and basic shell facilities, such as Input/Output (I/O) redirection and pipes.

Implementations of the language are available for many different computing environments. This book, while describing the language in general, also describes a particular implementation of  called  (which stands for "GNU Awk"). runs on a broad range of Unix systems, ranging from 80386 PC-based computers, up through large scale systems, such as Crays. has also been ported to MS-DOS and OS/2 PC's, Atari and Amiga micro-computers, and VMS.

History of and

The name comes from the initials of its designers: Alfred V. Aho, Peter J. Weinberger, and Brian W. Kernighan. The original version of was written in 1977 at AT&T Bell Laboratories. In 1985 a new version made the programming language more powerful, introducing user-defined functions, multiple input streams, and computed regular expressions. This new version became generally available with Unix System V Release 3.1. The version in System V Release 4 added some new features and also cleaned up the behavior in some of the "dark corners" of the language. The specification for in the POSIX Command Language and Utilities standard further clarified the language based on feedback from both the  designers, and the original Bell Labs awk designers.

The GNU implementation,, was written in 1986 by Paul Rubin and Jay Fenlason, with advice from Richard Stallman. John Woods contributed parts of the code as well. In 1988 and 1989, David Trueman, with help from Arnold Robbins, thoroughly reworked for compatibility with the newer. Current development focuses on bug fixes, performance improvements, standards compliance, and occasionally, new features.

The GNU Project and This Book

The Free Software Foundation (FSF) is a non-profit organization dedicated to the production and distribution of freely distributable software.