in reply to Script to Notify of Public IP Change
"unsure of whether or not their ISP provided them with a static or dynamic IP address"
Have you tried asking them? Or having the Police ask them on your behalf, as they are the customer? I'd consider using Dynamic_DNS, rather than reply on finding out changes via a cron job.
"Sometimes, it seems to fetch a "blank" when trying to resolve the IP"
Add some checking in your code, ensure $ip is a valid IP address, handle any errors accordingly.
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