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The Evolution of the awk Language

This manual describes the GNU implementation of awk, which is patterned after the POSIX specification. Many awk users are only familiar with the original awk implementation in Version 7 Unix, which is also the basis for the version in Berkeley Unix (through 4.3--Reno). This chapter briefly describes the evolution of the awk language.

Major Changes between V7 and S5R3.1

The awk language evolved considerably between the release of Version 7 Unix (1978) and the new version first made widely available in System V Release 3.1 (1987). This section summarizes the changes, with cross-references to further details.

Changes between S5R3.1 and S5R4

The System V Release 4 version of Unix awk added these features (some of which originated in gawk):

Changes between S5R4 and POSIX awk

The POSIX Command Language and Utilities standard for awk introduced the following changes into the language:

Extensions in gawk not in POSIX awk

The GNU implementation, gawk, adds these features:

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