php shell_exec touch redirect and adduser

Question

I am trying to ultimately use php\'s shell_exec function to create new Linux users. I am, however, running into problems even with the debugging. Here is my code

Answer 1

• Many (most?) of PHP's internal functions don't throw exceptions, they raise errors. I don't think you will ever see an exception thrown by shell_exec()
• I might var_dump() the return value, just to ensure you're explicitly aware of what it's returned.
• I would also suggest looking into functions like escapeshellarg() to avoid issues with your input.

As a general case, rather than having PHP execute several commands sequentially, I write a shell script that does everything I need, then call it from PHP. There's one fewer link in the chain when debugging, and I find I a lot easier.

With regards to your SSH command itself, since apache is executing as www-data, how is it logging into the machine in question as root? Have you added the apache user's key to the remote machine.

Answer 2

Please use my function found here.

Run the following code and tell us its output:

echo '<pre>';
print_r(execute('pwd'));
print_r(execute('touch test.txt'));

Edit: If you want to make my script more OO oriented:

function execute_o($cmd,$in){
    $out=execute($cmd,$in);
    if($out['return']!=0)
        throw new Exception('Error '.$out['return'].': '.$out['stderr'].'.');
}