Debian `hosts` updater for DNS block

stevenblackhosts

#!/bin/sh

set -e

tmp="$(mktemp)"
file="/etc/hosts"

wget --quiet -O "${tmp}" https://raw.githubusercontent.com/StevenBlack/hosts/master/alternates/fakenews-gambling/hosts

if [ ! -s "$file" ]; then
        exit 0
fi

sed -i 's/\(\slocalhost\)$/\1 '"$(hostname)"'/g' "${tmp}"

if cmp --silent -- "${file}" "${tmp}"; then
        rm --force "${tmp}"
        exit 0
fi

chown --reference="${file}" "${tmp}"
chmod --reference="${file}" "${tmp}"
mv --no-target-directory --force "${tmp}" "${file}"