#! /bin/sh
#
# Returns a grep pattern for matching the IP addresses of the given hosts.
# Note that generally when using the pattern you should surround it with
# some form of anchoring, such as blanks, to avoid false hits.

sheesh=`(for i do host-to-addrs $i; done)`
if [ "$sheesh" = "" ]; then exit 1; fi;
echo "$sheesh" | xargs | sed 's/\./\\./g;s/ /|/g;s/.*/(&)/'