title: How do I detect if the system time is changed? (from .net)
body: <p>I am using DateTime.UtcNow to measure time in my software and need to be able to tell if “action a” happens less more than 10 seconds after “action b”</p>
  
  <p>However what if the system time is change?  So how I do I detect if the system time is changed?</p>
  
  <p>I don’t wish to use a stopwatch as we need to run on servers with more then one CPU, see <a href="http://kristofverbiest.blogspot.com/2008/10/beware-of-stopwatch.html" rel="noreferrer">http://kristofverbiest.blogspot.com/2008/10/beware-of-stopwatch.html</a> </p>
  
  <p>I also need to cope with virtual machines being paused and restarted, so the “tick count” is unlikely to be useful to me.</p>