Gridfire is inspired by gpggrid, a security tool included in Tinfoil Hat Linux
(http://tinfoilhat.shmoo.com) intended to resist shoulder-surfing and keylogging.
For more information on the project, see the README file distributed with Gridfire.

Gridfire is named after a fictional superweapon in Iain M Banks' Culture novels.
See http://everything2.com/title/Gridfire for more.
RIP Iain M Banks (1954-02-16 to 2013-06-09)

usage: gridfire.py [-h] [-a TTYALERT] [-c] [-g] [-u] [-l] [-b] [-o] [-d] [-f]
                   [-p] [-w] [-m METHOD] [-n] [-v VERBOSITY] [-S SINGLE]
                   [-D DOUBLE] [-P POS] [-H HEADER] [-A ANSWER] [-O fd]
                   [STDIN COMMAND [STDIN ARGS ...]]

positional arguments:
  STDIN COMMAND         Arguments to run a subprocess wih the password in stdin.

optional arguments:
  -h, --help            show this help message and exit
  -a TTYALERT, --ttyalert TTYALERT
                        Set the alert mode (none, beep or flash)
  -c                    Force concealment of entered text.
  -g, --grid            Ignore other options and behave like gpggrid.
  -u                    Allow uppercase letters [A-Z].
  -l                    Allow lowercase letters [a-z].
  -b                    Allow binary numbers [0-1].
  -o                    Allow octal numbers [0-7].
  -d                    Allow decimal numbers [0-9].
  -f                    Allow hexadecimal numbers [0-9][a-f][A-F].
  -p                    Allow punctuation.
  -w                    Allow whitespace.
  -m METHOD, --method METHOD
                        Specify indexing method (0-3, higher is more secure,
                        default=3)
  -n                    Append a newline on output.
  -v VERBOSITY, --verbosity VERBOSITY
                        Specify verbosity (0-5, higher is verbose, default=3)
  -S SINGLE, --single SINGLE
                        Arg to pass to a subprocess with -SINGLE=password.
  -D DOUBLE, --double DOUBLE
                        Arg to pass to a subprocess with --DOUBLE=password.
  -P POS, --pos POS     Position to place the Arg to a subprocess with
                        --DOUBLE/SINGLE=password.
  -H HEADER, --header HEADER
                        Header line as a prompt (default "").
  -A ANSWER, --answer ANSWER
                        Skip the grid and give the answer (for testing only).

