Python & Linux, some questions (2)

[Luca T.]

Ok...
Now...
I made this simple program as a test:

import popen2
r,w,e = popen2.popen3('su -c ls')
for line in e.readlines():
	print 'E: ' + line
for line in r.readlines():
	print 'R: ' + line

r.close
w.close
e.close

In few words, it runs "su -c ls", and it should tell me what it writes 
in stdout and stderr.

Now... this is what i get:

[luca at ATH2000 tmp]$ python test.py
E: standard in must be a tty

So it seems that "su" refuses to work if it is run like this.
Now, beside "sudo" that i CANNOT use because i don't want to change the 
configuration of the user's comp... any idea about how i could run a 
program as root from inside my python program?

Thanx,
   Luca