gistfile1.sh

#!/bin/sh

if [ "x$#" != "x1" ]
then
	echo "usage: $0 depth"
	echo "depth: "
	exit 0
fi

depth=$1
loop=1
while [ $loop ]
do
	if [ "$depth" -lt "1" ]
	then
		echo "level of depth reached"
		exit
	fi

	current_unknown_keys=$(gpg --list-sigs | grep "User ID not found" | sed 's/.*\s\([0-9A-F]*\)\s....-..-...*/\1/' | sort | uniq)
	if [ $(echo "$current_unknown_keys" | wc -l) -ne "0" ]
	then
		for key in $current_unknown_keys
		do
			echo "fetching key $key"
			gpg --keyserver "hkp://pool.sks-keyservers.net" --recv-key $key  1> /dev/null 2>/dev/null
		done
	else
		loop=0
	fi

	depth=$(expr $depth - 1)
done