title: Open executable with php
body: <p>How to open executable (GNU/Linux) with php? </p>
  
  <p><code>exec</code> and <code>system</code> are not working for me.</p>
  
  <p>Since I have tried multiple different options, I'm here to ask you. I never had any experience with php (I work with C), so I'm stuck at probably something simple, yet so hard for me. I have tried this: </p>
  
  <pre><code>&lt;?php
  
  string exec('add_user email password');
  
  ?&gt;
  </code></pre>
  
  <p>and many other possibilities.
  add_user is an executable written in C++. It is located in root folder, in html folder and apache2 folder (just in case), so it's not the path at fault. Email and password are parameters. I have tried both exec() and system(), nothing happens. I have even tried 'whoami', nothing. When I says nothing happens, I really mean it. I call the php with browser "localhost/test.php", just get blank site. If I try <code>echo 'string';</code> i still get nothing. </p>