title: ErrorException: Warning: ini_set(): A session is active. You cannot change the session module's ini settings at this time in /../../
body: <p>I am trying to create my own authentication provider like in <a href="http://symfony.com/doc/current/cookbook/security/custom_authentication_provider.html" rel="nofollow">http://symfony.com/doc/current/cookbook/security/custom_authentication_provider.html</a>.</p>
  
  <p>But, it keeps saying:</p>
  
  <p>ErrorException: Warning: ini_set(): A session is active. You cannot change the session module's ini settings at this time in /../../vendor/symfony/symfony/src/Symfony/Component/HttpFoundation/Session/Storage/Handler/NativeFileSessionHandler.php line 56</p>