#!/bin/bash

# check delay (seconds)
CHECKDELAY=5

CURRENTIP="$(lynx --dump checkip.dyndns.org | awk '/IP/{ print $NF; }')"

logger -t ipupdater "Started. Current official IP: $CURRENTIP; Scan delay: $CHECKDELAY seconds."

while sleep $CHECKDELAY; do
   NEWIP="$(lynx --dump checkip.dyndns.org | awk '/IP/{ print $NF; }')" 
   if [ "$CURRENTIP" != "$NEWIP" ]; then
       logger -t ipupdater "IP seems to have changed to $NEWIP. Calling ddclient."
       CURRENTIP="$NEWIP"
       echo call ddclient with proper options here
   fi
done