3v4l.org

run code in 300+ PHP versions simultaneously
<?php echo syscall("echo foo | grep foo"); function syscall($command){ $result = ""; if ($proc = popen("($command)2>&1","r")){ while (!feof($proc)) $result .= fgets($proc, 1000); pclose($proc); return $result; } } ?>
Output for 7.2.29 - 7.2.33, 7.3.16 - 7.3.33, 7.4.3 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
Warning: popen((echo foo | grep foo)2>&1,r): Cannot allocate memory in /in/rDAvv on line 7
Output for 4.3.0 - 4.3.11, 4.4.0 - 4.4.9, 5.0.0 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.0 - 5.5.37, 5.6.0 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.33, 7.2.0 - 7.2.24, 7.3.0 - 7.3.12, 7.4.0
preferences:
265.15 ms | 404 KiB | 394 Q