Problem in calling Python script from PHP

Question

This is my python script which creates a "test.txt" file when executed. when I execute using terminal (Ubuntu 11.04) root@gml-VirtualBox:/var/www/HMS# python test.py. It creates the "test.txt" in the /var/www/HMS directory as I expected.

test.py:
#!/usr/bin/env python
def init():
 filename = "test.txt"
 file = open(filename, 'w')
 file.write("This is the new content of test.txt :-)")
 file.close()
 print "done"
def main():
 init()
if __name__ == '__main__':
 main()

But when I try to call this test.py using PHP, It's not creating the 'test.txt' output file.

index.php:
$tmp = exec("python test.py");
echo "temp: $tmp";

Both test.py & index.php are in the same directory(/var/www/HMS/). But when I modified the test.py like this:

#!/usr/bin/env python
def init():
 print "done"
def main():
 init()
if __name__ == '__main__':
 main()

It prints temp: done in the browser, which is what I expected.

I don't know why my previous python code didn't work as expected.

Answer 1

When you test the python script on the command line, you're running as root. Chances are you're not running the webserver as root (which is a good thing), and the webserver's user does not have appropriate permissions to create and/or write to that file.

• Maggie: thanks alot for your answer Mat..Now I fixed that. However I have similar problem when executing nltk.WordNetLemmatizer() function. This time permission is not an issue, as I checked that after your suggestion. If you are familiar with NLTK library, can he help me with this
• slash89mf: How did you set permissions for webserver?
• shawn caza: A lot of shared server providers won't allow to use exec(). So you're python script will never be called at all this way.