title: Delaying for milliseconds in C++ cross-platform
body: <p>I'm writing a multi-platform internal library in C++ that will eventually run on Windows, Linux, MacOS, and an ARM platform, and need a way to sleep for milliseconds at a time.</p>
  
  <p>I have an accurate method for doing this on the ARM platform, but I'm not sure how to do this on the other platforms.</p>
  
  <p>Is there a way to sleep with millisecond resolution on most platforms or do I have to special-case things for each platform?</p>