3v4l.org

run code in 150+ php & hhvm versions
Bugs & Features
<?php system('w');
Output for 4.3.0, 5.4.43 - 5.6.28, 7.0.0 - 7.1.0
Output for hhvm-3.10.0 - 3.12.0
Failed to exec: `w'
Output for 4.3.1 - 5.4.42
sh: 1: w: not found