#!/bin/csh -f
#H# This script verifies that the reverse DNS for the IP address entered as
#H# the CLI param matches the forward DNS of the name that it points to.

set IP=$1
set Name=`dnsname $IP`
set RealIP=`dnsip $Name`

if ("$IP" == "$RealIP") then
  echo "$IP is $Name."
  exit 0
else
  echo "$IP claims to be $Name but it isn't because $RealIP is."
  exit 1
endif