title: UTC time in ticks (since 01/01/0001 00:00:00)
body: <p>I'm trying to integrate with a third party service that wants to know how many "UTC time in ticks (since 01/01/0001 00:00:00)" have passed.</p>
  
  <p>What is a tick?</p>
  
  <p>Assuming it's a second (and I don't know that it is)...  how am I supposed to do it since 01/01/0001 00:00:00? That's bigger than a 32-bit integer. Not sure if it's bigger than a 64-bit integer but PHP's date() functions return 32-bit integers - not 64-bit ones.</p>
  
  <p>If I knew how many seconds had elapsed between 01/01/0001 00:00:00 and UNIX epoch I could use bcmath or gmp to add that amount (as a constant) to time() (again assuming ticks are seconds) but I don't know what that number would be.</p>
  
  <p>Any ideas?</p>