#!/bin/bash
awk -F'[\t ]+' '{
if (!match($0, /^\s*(#|$)/)) {
if (NF>=2 && length($2)) {
host=$2
} else {
host=$1
}
if (!match(host, /^(localhost|local|localhost.localdomain|ip6-localnet|ip6-localhost$)$/)) {
print "127.0.0.1 " host
}' adlists/* > block.list