A shell script checking the public IP of the host it is run on, and uploading to to a git repository

updateip.sh

print_usage () {
    echo "USAGE: updateip.sh PATH FILE"
}

if [ -z "$1" ]; then
    print_usage
    exit 1
fi

if [ -z "$2" ]; then
    print_usage
    exit 1
fi

cwd="$(pwd)"
cd $1
git pull --force
ip="$(dig +short myip.opendns.com @resolver1.opendns.com)"
echo "$ip" > $2
diff="$(git diff)"
if [ -n "$diff" ]; then
    git add $2 --force
    git commit -m "$ip"
    git push --force
fi

cd "$cwd"