title: C++: one writer/multi reader access to an unordered_map thread safe?
body: <p>I would like to build an unordered_map with concurrent access from one writer and multiple read threads. The writer will ONLY INSERT a pair, not remove or update anything inserted. Is this one thread safe? Can I view the insertion operation as an atomic operation? I ran multiple tests on my code, no crash or incorrect results found. </p>
  
  <p>Thx!</p>