title: cpp - header file include error
body: <p>I have a c++ application which I want to use some external code in it.
  The external code is placed in a relative path "........\External" folder.
  The external code has a cpp file aaa.cpp which include bbb.h header file.</p>
  
  <p>I also have my own - changed - bbb.h file in my solution but I want that the aaa.cpp file will include MY bbb file and not thr bbb file in the external folder.
  It means that the aaa.cpp file is in my solution but is taken from "......\External"
  and the bbb.h file is also in my solution but without a relative path.</p>
  
  <p>I tried to compile it and the aaa.cpp file has an error on this line:</p>
  
  <pre><code>#include "bbb.h"
  </code></pre>
  
  <p>Error: cannot open source file bbb.h</p>
  
  <p>How can I solve this issue?</p>