Part IV:
Appendices

Appendix A The Evolution of the awk Language

This Web page describes the GNU implementation of awk, which follows the POSIX specification. Many longtime awk users learned awk programming with the original awk implementation in Version 7 Unix. (This implementation was the basis for awk in Berkeley Unix, through 4.3-Reno. Subsequent versions of Berkeley Unix, and, for a while, some systems derived from 4.4BSD-Lite, used various versions of gawk for their awk.) This chapter briefly describes the evolution of the awk language, with cross-references to other parts of the Web page where you can find more information.

• Major Changes Between V7 and SVR3.1
• Changes Between SVR3.1 and SVR4
• Changes Between SVR4 and POSIX awk
• Extensions in Brian Kernighan’s awk
• Extensions in gawk Not in POSIX awk
• History of gawk Features
• Common Extensions Summary
• Regexp Ranges and Locales: A Long Sad Story
• Major Contributors to gawk
• Summary