title: c++ no such file or directory - Visual Studio
body: <p>so I'm making a program that reads a file which name is specified by the command line argument in Visual studio, now I set the command argument in VS as "data5.txt" and already have that file in the source files folder, However it appears the code still thinks there's no such file or directory</p>
  
  <pre><code>std::string filename = argv[1];
  std::ifstream in(filename);
  if (!in.is_open())
      perror("error");
  </code></pre>