Mawk
Mawk is an implementation of AWK.
Other implementations of AWK.
mawk is Mike Brennan's awk. It is compatible with nawk and POSIX awk. It has at least one more feature: RS can be a regular expression.
mawk's interpreter tries to be fast. It translates each program to an internal bytecode. This program, to sum the numbers on each input line, becomes ten instructions of bytecode:
$ mawk -W dump '{ sum += $0 } END { print sum }' END 000 pushi sum 002 pushint 1 004 print 006 exit0 MAIN 000 omain 001 pusha sum 003 pushi $0 005 add_asg 006 pop 007 ol_gl
The last version from Mike Brennan was mawk 1.3.3. Thomas E Dickey revived the project and made mawk 1.3.4.