3v4l.org

run code in 150+ php & hhvm versions
Bugs & Features
<?php var_dump(`which php`);
Output for 5.4.44 - 5.6.28, 7.0.0 - 7.1.0
NULL
Output for hhvm-3.10.0 - 3.12.0
string(28) "Failed to exec: `which php' "
Output for 5.4.39 - 5.4.43
NULL /usr/bin/which: 3: exec: echo: not found
Output for 5.0.0 - 5.4.38
NULL sh: 1: which: not found
Output for 4.3.1 - 4.4.9
string(0) "" sh: 1: which: not found
Output for 4.3.0
string(0) ""