3v4l.org

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<?php session_start(); echo '<form method="POST">'; echo '<input type="submit" name="like" value="Like">'; echo '</form>'; ?>
Output for 5.2.3 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.0 - 5.5.35, 5.6.0 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
<form method="POST"><input type="submit" name="like" value="Like"></form>
Output for 4.4.3 - 4.4.9, 5.0.0 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0 - 5.2.2
<br /> <b>Warning</b>: session_start() [<a href='function.session-start'>function.session-start</a>]: Cannot send session cookie - headers already sent in <b>/in/nNO4s</b> on line <b>2</b><br /> <br /> <b>Warning</b>: session_start() [<a href='function.session-start'>function.session-start</a>]: Cannot send session cache limiter - headers already sent (output started at /in/nNO4s:2) in <b>/in/nNO4s</b> on line <b>2</b><br /> <form method="POST"><input type="submit" name="like" value="Like"></form>
Output for 4.3.2 - 4.3.11, 4.4.0 - 4.4.2
<br /> <b>Warning</b>: session_start(): Cannot send session cookie - headers already sent in <b>/in/nNO4s</b> on line <b>2</b><br /> <br /> <b>Warning</b>: session_start(): Cannot send session cache limiter - headers already sent (output started at /in/nNO4s:2) in <b>/in/nNO4s</b> on line <b>2</b><br /> <form method="POST"><input type="submit" name="like" value="Like"></form>
Output for 4.3.0 - 4.3.1
<br /> <b>Warning</b>: session_start() [<a href='http://www.php.net/function.session-start'>function.session-start</a>]: Cannot send session cookie - headers already sent in <b>/in/nNO4s</b> on line <b>2</b><br /> <br /> <b>Warning</b>: session_start() [<a href='http://www.php.net/function.session-start'>function.session-start</a>]: Cannot send session cache limiter - headers already sent (output started at /in/nNO4s:2) in <b>/in/nNO4s</b> on line <b>2</b><br /> <form method="POST"><input type="submit" name="like" value="Like"></form>

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