Basic "dynamic DNS" subdomain updater thingy

ddns.sh

#!/bin/bash

# Find your current IP address
ip=`dig +short myip.opendns.com @resolver1.opendns.com`

# Subdomain to update
subdomain="SUBDOMAIN_HERE"

# Example for Linode DNS
api_key="API_KEY_HERE"
api_call="https://api.linode.com/?api_key=$api_key&api_action=domain.resource.update"
api_call="$api_call&DomainID=DOMAIN_ID_HERE&Type=A&Target=$ip&Name=$subdomain"
api_call="$api_call&resourceid=RESOURCE_ID_HERE"

response=$(curl $api_call);
echo "$response";

Cheapskate cron-job.