title: Session callback expects true/false return value
body: <p>My php script, sometimes, give me the following error:</p>
  
  <pre><code>    Warning: session_start(): Session callback expects true/false return 
  value in C:\xampp\htdocs\verifica.php on line 10
  </code></pre>
  
  <p>verifica.php line 10:</p>
  
  <pre><code>if (session_status() == PHP_SESSION_NONE) {
      session_start(); //this is line 10
  }
  </code></pre>
  
  <p>what is wrong? why I have this error? this only shows when it wants, not always...</p>