title: Test memory leak by instruments of Xcode
body: <p>Can I use Xcode instruments to test memory leak of a C++ command line tool?</p>
  
  <p>I tried to do so, and I cannot find a console to use <code>cin</code>.</p>
  
  <p>However, for a iOS app, there will be a simulator so that we can do something to our program.</p>