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run code in 150+ php & hhvm versions
Bugs & Features
<?php session_start(); $_SESSION["\0"] = null; var_dump(array_keys($_SESSION));
Output for 5.2.3 - 7.1.0
array(1) { [0]=> string(1) "" }
Output for 4.3.2 - 5.2.2
Warning: session_start(): Cannot send session cookie - headers already sent in /in/fUvPl on line 2 Warning: session_start(): Cannot send session cache limiter - headers already sent (output started at /in/fUvPl:2) in /in/fUvPl on line 2 array(1) { [0]=> string(1) "" }
Output for 4.3.0 - 4.3.1
Warning: session_start() [http://www.php.net/function.session-start]: Cannot send session cookie - headers already sent in /in/fUvPl 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/fUvPl:2) in /in/fUvPl on line 2 array(1) { [0]=> string(1) "" }