How do I convert boost::posix_time::ptime to time_t?

Question

Is there some \"standard\" way or the best I can do is to compute it directly by subtracting from gregorian::date(1970,1,1)?

Answer 1

Here's a variation of @ybungalobill's method that will get you past 2038, just in case. :)

int64_t rax::ToPosix64(const boost::posix_time::ptime& pt)
{
  using namespace boost::posix_time;
  static ptime epoch(boost::gregorian::date(1970, 1, 1));
  time_duration diff(pt - epoch);
  return (diff.ticks() / diff.ticks_per_second());
}