title: How to flush file buffers when using boost::serialization?
body: <p>I'm saving a file on an USB drive and need to make sure that it's completely written to avoid corruption in case the USB drive is not removed properly.
  Well I've done some research and it seems this is possible via calling the FlushFileBuffers Win32 function.
  But the problem is, I'm saving using boost::serialization and thus don't have access to the actual file HANDLE. 
  I wonder what is the proper way to flush the file? Thanks!</p>