title: Fastest way to check if a file exists using standard C++/C++11,14,17/C?
body: <p>I would like to find the fastest way to check if a file exists in standard C++11, 14, 17, or C. I have thousands of files and before doing something on them I need to check if all of them exist. What can I write instead of <code>/* SOMETHING */</code> in the following function?</p>
  <pre><code>inline bool exist(const std::string&amp; name)
  {
      /* SOMETHING */
  }
  </code></pre>