title: Read access violation error on trying to open a file
body: <p>I am trying to check if a file exists by opening it with fopen() and then checking if the function returns <code>NULL</code>. But when I run the code, it says a read access violation error accured, but I don't get why, since I checked and the file I am trying to read is txt and has text already written in it. Can someone explain why and how I can fix it?</p>
  
  <pre><code>int main(int argc, char** argv)
  {
      int quit = FALSE;
      if (fopen(*(argv+2), 'r') == NULL)
      {
          printf("Invalid input! File does not exit.");
          quit = TRUE;
      }
  }
  </code></pre>