How to run a perl script from php with variables

Question

I am trying to run a perl script from php that requires parameters to be passed to the perl script to run correctly. The following is the correct usage of the perl script from the linux terminal:

/home/user/test.pl -a alpha -b beta

or just

/home/user/test.pl -a alpha

I have execute permissions on the script and can run it without any parameters and the correct usage from the script is displayed back to my browser.

Below is the PHP code that works by displaying the usage back to my browser:

$result = shell_exec('/home/user/test.pl');
echo $result;

And the following is the problem code which I can not for the life of me figure out:

$test = $_POST['test'];
$result = shell_exec('/home/user/test.pl -a'.' '.$test);
echo $result;

Can anyone tell me what it is that I am missing to make this work correctly?

Thank you for the help.

The webserver runs under it's own user account and likely won't have access to another user's home directory. If the webserver is apache, the user is usually "apache". You would need to move the script to somewhere that the user apache can reach and make sure the script permissions allow apache to execute the file. — Jonathan Kuhn, Mar 31 '15 at 21:17
@JonathanKuhn But the OP says the code works when they don't pass any arguments... — ThisSuitIsBlackNot, Mar 31 '15 at 21:18
What exactly "isn't working"? Are you getting the wrong output? No output at all? Any errors? — ThisSuitIsBlackNot, Mar 31 '15 at 21:20
What is being posted back to the page, specifically what is the value of `$test`? — Professor of programming, Mar 31 '15 at 21:22
There is nothing from the script coming back to the web page other than the html that I put at the top of the page outside of the php. — nerdyoutdoorsman, Mar 31 '15 at 21:29
$test comes from a text input from an html page. It is typically someones account such as joeid. — nerdyoutdoorsman, Mar 31 '15 at 21:30
Have you tried using passthru instead of shell_exec to see what the actual output is? — Professor of programming, Mar 31 '15 at 21:32
Also to clarify. I created a hello_world.pl script, matched the permissions to the other script and placed it in the same directory and it printed Hello World to my browser. So it is 100% not a permission issue. — nerdyoutdoorsman, Mar 31 '15 at 21:32
@Bonner what would that look like exactly? I have not used passthru before. — nerdyoutdoorsman, Mar 31 '15 at 21:33
Don't forget to [sanitize your input](http://stackoverflow.com/q/129677/176646) for people with usernames like `foo && echo mwahahaha` — ThisSuitIsBlackNot, Mar 31 '15 at 21:50
Sorry but it is not working to just swap out passthru with shell_exec. — nerdyoutdoorsman, Apr 01 '15 at 00:24
What do you mean it is not working? Can you actually say what is not working? — Professor of programming, Apr 01 '15 at 04:01
Sure, when the web browser is loaded to the php page it is only showing the HTML that I have placed at the top. I am not seeing any output from the script. When I go to the server the script has not been ran when I do a ps -ef | grep account that runs this script. This script takes about 35 seconds to complete. — nerdyoutdoorsman, Apr 01 '15 at 13:02

score 0 · Accepted Answer · answered Apr 01 '15 at 15:14

My issue resided within the perl script itself and a specific line that was trying to output to a log file which the apache user did not have access to. I was calling the script correctly the whole time but once I was able to get to the server side logs (granted by system admin) I saw the issue was buried within the Perl script and not in php.

How to run a perl script from php with variables

1 Answers1