There are two ways to run awk—with an explicit program or with one or more program files. Here are templates for both of them; items enclosed in [...] in these templates are optional:
awk [options] -f progfile [
--] file ... awk [options] [
--] 'program' file ...
Besides traditional one-letter POSIX-style options, gawk also supports GNU long options.
It is possible to invoke awk with an empty program:
awk '' datafile1 datafile2
Doing so makes little sense, though; awk exits silently when given an empty program. (d.c.) If --lint has been specified on the command line, gawk issues a warning that the program is empty.