#!/bin/bash

timezone=$(/usr/sbin/systemsetup -gettimezone | awk '{ print $3 }')
/usr/sbin/systemsetup -setusingnetworktime Off -settimezone GMT -setdate 01:01:1970 -settime 00:00 > /dev/null
sudo -k
sudo /usr/sbin/systemsetup -setusingnetworktime On -settimezone $timezone > /dev/null; sudo /bin/bash