title: Is std::ifstream thread-safe & lock-free?
body: <p>I intend to perform opening for reading a single file from many threads using std::ifstream. My concern is if std::ifstream is thread-safe &amp; lock-free?</p>
  
  <p>More details:</p>
  
  <ol>
  <li>I use g++ 4.4 on Ubuntu &amp; Windows XP, 4.0 on Leopard.</li>
  <li>Each thread creates its own instance of std::ifstream</li>
  </ol>
  
  <p>Thanks in advance!</p>