php system（）函数无法使用

Question

I just use the document example code to test.

<?php
    echo '<pre>';
    $last_line = system('ls', $retval);

    echo '
    </pre>
    <hr />Last line of the output: ' . $last_line . '
    <hr />Return value: ' . $retval;
?>

But on the result is this

And I remove the system in disable_function of php.ini. But it is still no use.

Answer 1

There are three key reasons why your code is probably not working:

1. There is an illegal character in your code. Chances are, errors are disabled, however PHP is halting. Remove 。 on the first line of your PHP.

2. If you are on Windows, ls is not a valid command - it only works on *nix systems (Linux, Unix / macOS). You'll have to replace ls with dir.

3. Finally, if it still does not work, you must have not enabled the use of system correctly. Double-check that disable_functions in your php.ini file does not have system listed, and then restart your Apache server.