-f program-file, --file program-file

Read the AWK program source from the file program-file, instead of from the first command line argument. Multiple -f (or --file) options may be used.

-F fs, --field-separator fs

Use fs for the input field separator (the value of the FSpredefined variable).

-v var=val, --assign var=val

Assign the value val to the variable var, before execution of the program begins. Such variable values are available to the BEGIN block of an AWK program.

-b, --characters-as-bytes

Treat all input data as single-byte characters. In other words, don't pay any attention to the locale information when attempting to process strings as multibyte characters. The --posix option overrides this option.

-c, --traditional

Run in compatibility mode. In compatibility mode, gawk behaves identically to UNIX awk; none of the GNU-specific extensions are recognized. See GNU EXTENSIONS, below, for more information.

-C, --copyright

Print the short version of the GNU Copyright information message on the standard output and exit successfully.

-d[file], --dump-variables[=file]

Print a sorted list of global variables, their types and final values to file. If no file is provided, gawk uses a file named awkvars.out in the current directory. Having a list of all the global variables is a good way to look for typographical errors in your programs. You would also use this option if you have a large program with a lot of functions, and you want to be sure that your functions don't inadvertently use global variables that you meant to be local. This is a particularly easy mistake to make with simple variable names like i, j, and so on.

-e program-text, --source program-text

Use program-text as AWK program source code. This option allows the easy intermixing of library functions (used via the -f and --file options) with source code entered on the command programs used in shell scripts.

-E file, --exec file

Similar to -f, however, this is option is the last one processed. This should be used with #! scripts, particularly for CGI applications, to avoid passing in options or source code (!!!) on the command line from a URL. This option disables command-line variable assignments.

-g, --gen-pot

Scan and parse the AWK program, and generate a GNU .pot (Portable Object Template) format file on standard output with entries for all localizable strings in the program. The program itself is not executed. See the GNU gettext distribution for more information on .pot files.

-h, --help

Print a relatively short summary of the available options on the standard output. Per the GNU Coding Standards, these options cause an immediate, successful exit.

-L [value], --lint[=value]

Provide warnings about constructs that are dubious or non-portable to other AWK implementations. With an optional argument of fatal, lint warnings become fatal errors. This may be drastic, but its use will certainly encourage the development of cleaner AWK programs. With an optional argument of invalid, only warnings about things that are actually invalid are issued. Note: This is not fully implemented yet.

-n, --non-decimal-data

Recognize octal and hexadecimal values in input data. Use this option with great caution!

-N, --use-lc-numeric

This forces gawk to use the locale's decimal point character when parsing input data. Although the POSIX standard requires this behavior, and gawk does so when --posix is in effect, the default is to follow traditional behavior and use a period as the decimal point, even in locales where the period is not the decimal point character. This option overrides the default behavior, without the full draconian strictness of the --posix option.

-O, --optimize

Enable optimizations upon the internal representation of the program. Currently, this includes just simple constant-folding. The gawk maintainer hopes to add additional optimizations over time.

-p[prof_file], --profile[=prof_file]

Send profiling data to prof_file. The default is awkprof.out. When run with gawk, the profile is just a "pretty printed" version of the program. When run with pgawk, the profile contains execution counts of each statement in the program in the left margin and function call counts for each user-defined function.

-P, --posix

This turns on compatibility mode, with the following additional restrictions:

\x escape sequences are not recognized

Only space and tab act as field separators when FS is set to a single space, newline does not

You cannot continue lines after ? and :

The synonym func for the keyword function is not recognized

The operators ** and **= cannot be used in place of ^and ^=

The fflush() function is not available

-r, --re-interval

Enable the use of interval expressions in regular expression matching. Interval expressions were not traditionally available in the AWK language. The POSIX standard added them, to make awk and egrep consistent with each other. They are enabled by default, but this option remains for use with --traditional.

-R, --command file

Dgawk only. Read stored debugger commands from file.

-S, --sandbox

Runs gawk in sandbox mode, disabling the system()function, input redirection with getline, output redirection with print and printf, and loading dynamic extensions. Command execution (through pipelines) is also disabled. This effectively blocks a script from accessing local resources (except for the files specified on the command line).

-t, --lint-old

Provide warnings about constructs that are not portable to the original version of Unix awk.

-V, --version

Print version information for this particular copy of gawk on the standard output. This is useful mainly for knowing if the current copy of gawk on your system is up to date with respect to whatever the Free Software Foundation is distributing. This is also useful when reporting bugs. Per the GNU Coding Standards, these options cause an immediate, successful exit.

--

Signal the end of options. This is useful to allow further arguments to the AWK program itself to start with a "-". This provides consistency with the argument parsing convention used by most other POSIX programs.