3v4l.org

run code in 200+ php & hhvm versions
Bugs & Features
<?php echo exec('echo 123');
Output for 5.6.28, 7.0.14 - 7.3.0alpha1
Output for 4.3.2 - 5.6.25, 7.0.0 - 7.0.10
Warning: exec(): Unable to fork [echo 123] in /in/6ToAk on line 3
Output for 4.3.0 - 4.3.1
Warning: exec() [http://www.php.net/function.exec]: Unable to fork [echo 123] in /in/6ToAk on line 3