By Paul Rubin and Jay Fenlason
Gawk is the GNU Project's implementation of the AWK programming language. It conforms to the definition of the language in the POSIX 1003.2 Command Language And Utilities Standard. This version in turn is based on the description in The AWK Programming Language, by Aho, Kernighan, and Weinberger, with the additional features found in the System V Release 4 version of UNIX awk. Gawk also provides more recent Bell Laboratories awk extensions, and a number of GNU-specific extensions.
Pgawk is the profiling version of gawk. It is identical in every way to gawk, except that programs run more slowly, and it automatically produces an execution profile in the file awkprof.out when done. See the --profile option, below.
The command line consists of options to gawk itself, the AWK program text (if not supplied via the -f or --file options), and values to be made available in the ARGC and ARGV pre-defined AWK variables.