Linux® Desk Reference, Second Edition

Tools

awk

Awk is a scripting language that is best suited for bulk modification and formatting of text files. Generally speaking, awk scripts move through a text file looking for patterns and perform some sort of modification (or insertion or deletion) on the pattern when found.

Awk comes in several flavors including:

awk:	The original ca. 1977 scripting language named after its creators, Alfred Aho, Brian Kernighan, and Peter Weinberger.
nawk:	New awk, a 1985 improvement of the original programming language.
gawk:	GNU awk, the GNU implementation of the awk programming language.

Awk programs are always invoked from a command line starting with the word awk. Next on the command line comes either a pattern/action sequence enclosed in quotes or ...