title: How to retrieve the thread id from a boost::thread?
body: <p>I want to be able to identify threads by a simple id when logging so that it is easy to trace the execution of a single thread.  With windows using the API <code>GetCurrentThreadId()</code> can achieve what I want.  In <code>boost::thread</code> there is a method <code>get_id()</code> but this doesn't represent an integral value like an integer.  This object does have a thread_data member which contains an id which seems to be what I want but the data member is private so can't be accessed.</p>
  
  <p>What is the boost way to access the thread id for display or identification purposes?</p>