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run code in 200+ php & hhvm versions
Bugs & Features
<?php @header('X-foo: bar'); @session_id('foobar'); @session_id(''); var_dump(session_id()); ?>
based on sulUp
Output for 5.6.0 - 5.6.30, hhvm-3.18.5 - 3.22.0, 7.0.0 - 7.1.10
string(0) ""