3v4l.org

run code in 150+ php & hhvm versions
Bugs & Features
<?php header( 'Content-type: text/plain' ); error_reporting(-1); echo 'foo'; session_start(); header( 'Content-encoding: UTF-8' );
Output for 5.2.3 - 5.6.23, 7.0.0 - 7.1.0
foo Warning: session_start(): Cannot send session cookie - headers already sent by (output started at /in/hn73R:4) in /in/hn73R on line 5 Warning: session_start(): Cannot send session cache limiter - headers already sent (output started at /in/hn73R:4) in /in/hn73R on line 5 Warning: Cannot modify header information - headers already sent by (output started at /in/hn73R:4) in /in/hn73R on line 6
Output for hhvm-3.10.0 - 3.12.0
foo Warning: Cannot modify header information - headers already sent in /in/hn73R on line 6
Output for 4.3.2 - 5.2.2
foo Warning: session_start(): Cannot send session cookie - headers already sent by (output started at /in/hn73R:4) in /in/hn73R on line 5 Warning: session_start(): Cannot send session cache limiter - headers already sent (output started at /in/hn73R:4) in /in/hn73R on line 5
Output for 4.3.0 - 4.3.1
foo Warning: session_start() [http://www.php.net/function.session-start]: Cannot send session cookie - headers already sent by (output started at /in/hn73R:4) in /in/hn73R on line 5 Warning: session_start() [http://www.php.net/function.session-start]: Cannot send session cache limiter - headers already sent (output started at /in/hn73R:4) in /in/hn73R on line 5