title: Boost serialization end of file
body: <p>I serialize multiple objects into a binary archive with Boost.
  When reading back those objects from a <code>binary_iarchive</code>, is there a way to know how many objects are in the archive or simply a way to detect the end of the archive ?</p>
  
  <p>The only way I found is to use a try-catch to detect the stream exception.
  Thanks in advance.</p>