title: Inputs to sleep_until()
body: <p>As per an answer to my <a href="https://stackoverflow.com/questions/17563412/perform-function-at-certain-clock-time/17565485?noredirect=1#17565485">previous question</a>, I am trying to use <code>sleep_until()</code> but cannot find a tutorial that tells me how to use it with an actual time such as 1400:00h.</p>
  
  <p>There are examples like this: <code>std::this_thread::sleep_until(system_clock::now() + seconds(10));</code>, but I would like something that actually lets me specify a clock time. What format should this be in? I would appreciate any examples. </p>