3v4l.org

run code in 300+ PHP versions simultaneously
<?php if ( file_exists("/etc/hosts") ){ echo "This is a linux system\n"; if(is_callable("system")){ echo "System is available\n"; }elseif(is_callable("shell_exec")){ echo "Shell_exec is available\n"; }elseif(is_callable("exec")){ echo "exec is available\n"; }else{ echo "No dice:(";} }else{ echo "blah!\n\n"; } ?>

preferences:
42.47 ms | 402 KiB | 5 Q