3v4l.org

run code in 300+ PHP versions simultaneously
<?php session_start(); $old_sessionid = session_id(); session_regenerate_id(); $new_sessionid = session_id(); var_dump($old_sessionid === $new_sessionid);
Output for 5.2.3 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.24 - 5.5.35, 5.6.8 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.25, 7.2.0 - 7.2.33, 7.3.0 - 7.3.29, 7.4.0 - 7.4.22, 8.0.0 - 8.0.8
bool(false)
Output for 4.4.3 - 4.4.9, 5.2.0 - 5.2.2
Warning: session_start(): Cannot send session cookie - headers already sent in /in/4kXsa on line 2 Warning: session_start(): Cannot send session cache limiter - headers already sent (output started at /in/4kXsa:2) in /in/4kXsa on line 2 Warning: session_regenerate_id(): Cannot regenerate session id - headers already sent in /in/4kXsa on line 6 bool(true)
Output for 4.3.2 - 4.3.11, 4.4.0 - 4.4.2, 5.0.0 - 5.0.5, 5.1.0 - 5.1.6
Warning: session_start(): Cannot send session cookie - headers already sent in /in/4kXsa on line 2 Warning: session_start(): Cannot send session cache limiter - headers already sent (output started at /in/4kXsa:2) in /in/4kXsa on line 2 Warning: session_regenerate_id(): Cannot send session cookie - headers already sent by (output started at /in/4kXsa:2) in /in/4kXsa on line 6 bool(false)
Output for 4.3.1
Warning: session_start() [http://www.php.net/function.session-start]: Cannot send session cookie - headers already sent in /in/4kXsa on line 2 Warning: session_start() [http://www.php.net/function.session-start]: Cannot send session cache limiter - headers already sent (output started at /in/4kXsa:2) in /in/4kXsa on line 2 Fatal error: Call to undefined function: session_regenerate_id() in /in/4kXsa on line 6

preferences:
547.81 ms | 539 KiB | 20 Q