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<?php var_dump($_SESSION); session_start(); $_SESSION["test"] = 123; var_dump($_SESSION); session_write_close(); $_SESSION["test"] = 123456; var_dump($_SESSION);
Output for 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.7
Warning: Undefined global variable $_SESSION in /in/VQtQC on line 2 NULL Warning: session_start(): Session cannot be started after headers have already been sent in /in/VQtQC on line 3 array(1) { ["test"]=> int(123) } array(1) { ["test"]=> int(123456) }
Output for 8.0.0 - 8.0.30
Warning: Undefined variable $_SESSION in /in/VQtQC on line 2 NULL Warning: session_start(): Session cannot be started after headers have already been sent in /in/VQtQC on line 3 array(1) { ["test"]=> int(123) } array(1) { ["test"]=> int(123456) }
Output for 7.2.0 - 7.2.33, 7.3.12 - 7.3.31, 7.4.0 - 7.4.33
Notice: Undefined variable: _SESSION in /in/VQtQC on line 2 NULL Warning: session_start(): Cannot start session when headers already sent in /in/VQtQC on line 3 array(1) { ["test"]=> int(123) } array(1) { ["test"]=> int(123456) }
Output for 7.3.32 - 7.3.33
NULL Warning: session_start(): Cannot start session when headers already sent in /in/VQtQC on line 3 array(1) { ["test"]=> int(123) } array(1) { ["test"]=> int(123456) }
Output for 5.0.4 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0 - 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 - 7.1.20
Notice: Undefined variable: _SESSION in /in/VQtQC on line 2 NULL Warning: session_start(): Cannot send session cookie - headers already sent by (output started at /in/VQtQC:2) in /in/VQtQC on line 3 Warning: session_start(): Cannot send session cache limiter - headers already sent (output started at /in/VQtQC:2) in /in/VQtQC on line 3 array(1) { ["test"]=> int(123) } array(1) { ["test"]=> int(123456) }
Output for 4.3.2 - 4.3.11, 4.4.0 - 4.4.9, 5.0.0 - 5.0.3
Notice: Undefined variable: _SESSION in /in/VQtQC on line 2 NULL Warning: session_start(): Cannot send session cookie - headers already sent by (output started at /in/VQtQC:2) in /in/VQtQC on line 3 Warning: session_start(): Cannot send session cache limiter - headers already sent (output started at /in/VQtQC:2) in /in/VQtQC on line 3 array(1) { ["test"]=> int(123) } array(1) { ["test"]=> int(123456) }
Output for 4.3.0 - 4.3.1
Notice: Undefined variable: _SESSION in /in/VQtQC on line 2 NULL Warning: session_start() [http://www.php.net/function.session-start]: Cannot send session cookie - headers already sent by (output started at /in/VQtQC:2) in /in/VQtQC on line 3 Warning: session_start() [http://www.php.net/function.session-start]: Cannot send session cache limiter - headers already sent (output started at /in/VQtQC:2) in /in/VQtQC on line 3 array(1) { ["test"]=> int(123) } array(1) { ["test"]=> int(123456) }

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