#!/bin/sh -e
outfile="$1"
if [ -z "$outfile" ]; then
	echo >&2 usage: `basename $0` outfile
	echo >&2 ' outfile should be on a removable flash disk or similar'
	exit 1
fi

echo 'this uses /dev/random, so please keep using your computer to generate entropy'
head -c 3705 /dev/random | uuencode -m - | head -n 66 | tail -n 65 |
  gpg --s2k-count 8388608 --symmetric -a >"$outfile"