automatically update boot2docker ip in /etc/hosts

docker.sh

#!/bin/bash
# Usage:
#  git clone https://gist.github.com/ea78bb56d5bd901187dc.git docker.gist
#  mkdir ~/bin
#  ln -s docker.gist/docker.sh ~/bin/docker
#  export PATH=$PATH:~/bin
/usr/local/bin/docker "$@"
r=$?

update_boot2docker_ip() {
	IP=`boot2docker ip`

	if grep -q 'boot2docker$' /etc/hosts; then
		sudo sed -i '' -E "s/^[0-9\.]+ boot2docker$/${IP/./\\.} boot2docker/" /etc/hosts
	else
		sudo sh -c "echo '${IP} boot2docker' >> /etc/hosts"
	fi
}

if [ $r == "0" ]; then
	update_boot2docker_ip
fi

exit $r