B.6 Other Freely Available awk Implementations

It's kind of fun to put comments like this in your awk code.
// Do C++ comments work? answer: yes! of course
Michael Brennan

There are three other freely available awk implementations. This section briefly describes where to get them:

Unix awk

Brian Kernighan has made his implementation of awk freely available. You can retrieve this version via the World Wide Web from his home page.(64) It is available in several archive formats:

Shell archive

http://cm.bell-labs.com/who/bwk/awk.shar

Compressed tar file

http://cm.bell-labs.com/who/bwk/awk.tar.gz

Zip file

http://cm.bell-labs.com/who/bwk/awk.zip

This version requires an ISO C (1990 standard) compiler; the C compiler from GCC (the GNU Compiler Collection) works quite nicely.

See section Extensions in the Bell Laboratories awk, for a list of extensions in this awk that are not in POSIX awk.

mawk

Michael Brennan has written an independent implementation of awk, called mawk. It is available under the GPL (see section GNU General Public License), just as gawk is.

You can get it via anonymous ftp to the host ftp.whidbey.net. Change directory to `/pub/brennan'. Use "binary" or "image" mode, and retrieve `mawk1.3.3.tar.gz' (or the latest version that is there).

gunzip may be used to decompress this file. Installation is similar to gawk's (see section Compiling and Installing gawk on Unix).

mawk has the following extensions that are not in POSIX awk:

• The fflush built-in function for flushing buffered output (see section Input/Output Functions).

• The `**' and `**=' operators (see section Arithmetic Operators and also see Assignment Expressions).

• The use of func as an abbreviation for function (see section Function Definition Syntax).

• The `\x' escape sequence (see section 3.2 Escape Sequences).

• The `/dev/stdout', and `/dev/stderr' special files (see section Special File Names in gawk). Use "-" instead of "/dev/stdin" with mawk.

• The ability for FS and for the third argument to split to be null strings (see section Making Each Character a Separate Field).

• The ability to delete all of an array at once with `delete array' (see section The delete Statement).

• The ability for RS to be a regexp (see section How Input Is Split into Records).

• The BINMODE special variable for non-Unix operating systems (see section Using gawk on PC Operating Systems).

The next version of mawk will support nextfile.

awka

Written by Andrew Sumner, awka translates awk programs into C, compiles them, and links them with a library of functions that provides the core awk functionality. It also has a number of extensions.

The awk translator is released under the GPL, and the library is under the LGPL.

To get awka, go to http://awka.sourceforge.net. You can reach Andrew Sumner at [email protected].