#!/bin/bash
# Copyright (C) 2016 Ian Kelling

# chost: get canonical hostname

set -eE -o pipefail
trap 'echo "$0:$LINENO:error: \"$BASH_COMMAND\" returned $?" >&2' ERR

host=$1
addr=$(getent hosts $host | awk '{print $1}')
h=$(getent hosts $addr | awk '{print $2}')
echo ${h%%.*}