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Types of AWK
The AWK language was originally implemented as an AWK utility on Unix. Today, most Linux distributions provide GNU implementation of AWK (GAWK), and a symlink for AWK is created from the original GAWK binary. The AWK utility can be categorized into the following three types, depending upon the type of interpreter it uses for executing AWK programs:
- AWK: This is the original AWK interpreter available from AT&T Laboratories. However, it is not used much nowadays and hence it might not be well-maintained. Its limitation is that it splits a line into a maximum 99 fields. It was updated and replaced in the mid-1980s with an enhanced version called New AWK (NAWK).
- NAWK: This is AT&T's latest development on the AWK interpreter. It is well-maintained by one of the original authors of AWK - Dr. Brian W. Kernighan.
- GAWK: This is the GNU project's implementation of the AWK programming language. All GNU/Linux distributions are shipped with GAWK by default and hence it is the most popular version of AWK. GAWK interpreter is fully compatible with AWK and NAWK.
Beyond these, we also have other, less popular, AWK interpreters and translators, mentioned as follows. These variants are useful in operations when you want to translate your AWK program to C, C++, or Perl:
- MAWK: Michael Brennan interpreter for AWK.
- TAWK: Thompson Automation interpreter/compiler/Microsoft Windows DLL for AWK.
- MKSAWK: Mortice Kern Systems interpreter/compiler/for AWK.
- AWKCC: An AWK translator to C (might not be well-maintained).
- AWKC++: Brian Kernighan's AWK translator to C++ (experimental). It can be downloaded from: https://9p.io/cm/cs/who/bwk/awkc++.ps.
- AWK2C: An AWK translator to C. It uses GNU AWK libraries extensively.
- A2P: An AWK translator to Perl. It comes with Perl.
- AWKA: Yet another AWK translator to C (comes with the library), based on MAWK. It can be downloaded from: http://awka.sourceforge.net/download.html.