ddns.py

#!/usr/bin/env python

import urllib.request
import re, time, os

def getIP():
  try:
		with urllib.request.urlopen('http://myip.com.tw/') as f:
		     a = f.read().decode('utf-8')
	except:
		print ("network error")
		return lastIP

	return re.search("(\d+\.\d+\.\d+\.\d+)", a).group(1)

def updateIP():
	print(os.system("curl http://usn:[email protected]/ph/update"))

lastIP = getIP();
print(lastIP)
while True:

	time.sleep(30)

	IP = getIP();
	if IP != lastIP:
		lastIP = IP
		updateIP()
		print("updated")
	else:
		print("same")