Run a Linux System Command as a Superuser, Using a Python Script

Run a linux system command as a superuser, using a python script

You can either run your python script as root itself - then you won't need to add privilege to reload postfix.

Or you can configure sudo to not need a password for /etc/init.d/postfix.

sudo configuration (via visudo) allows NOPASSWD: to allow the command without a password. See http://www.sudo.ws/sudo/man/sudoers.html#nopasswd_and_passwd

<username>  ALL = NOPASSWD: /etc/init.d/postfix

or something similar.

How to run a command as root in python?

This package requires root permissions and root access. So, it must run as root and the package must be installed as root.

sudo commands are useful for this.

sudo python selenium_script.py
will run it as root. If this alone does not solve, you must install it as root too. Navigate to your terminal and cd to working directory (or home directory). Then, run this command:

sudo pip3 install keyboard # use pip if on python 2

running a command as a super user from a python script

Try giving the full path to apache2ctl.

Running python script as root

So you want the script to run as root, even without sudo? For that you would need to set the setuid bit on the script with sudo chmod u+s program. However, most Unix distributions allow this only for binaries, and not for scripts, for security reasons. In general it's really not a good idea to do that.

If you want to run this script as root, you will have to run as sudo. Or, you have to create a binary that runs your script, so that you can set the setuid bit on this binary wrapper. This related question explains more.

It's also a good idea to check the effective uid, and if it's not root then stop running. For that, add this near the top (thanks @efirvida for the tip!)

if not os.geteuid() == 0:
    sys.exit("\nOnly root can run this script\n")

ORIGINAL ANSWER

Maybe your user and root use a different version of python, with different python path, and different set of libraries.

Try this:

command -v python
sudo command -v python

If the two commands don't give the same result then you either need to change the setup of the users to use the same version of python (the one that has the ALSA libs), or hardcode the python version the first line of the script.

Also try adding a print sys.path line in the script, and run with your user and with sudo and compare. Probably you'll get different results. You may need to tweak the PYTHONPATH variable of your user.

It shouldn't be necessary to make the owner of the script root, and to run it with sudo. You just need to configure python and PYTHONPATH correctly.

Using sudo with Python script

sudoPassword = 'mypass'
command = 'mount -t vboxsf myfolder /home/myuser/myfolder'
p = os.system('echo %s|sudo -S %s' % (sudoPassword, command))

Try this and let me know if it works. :-)

And this one:

os.popen("sudo -S %s"%(command), 'w').write('mypass')

python run command as normal user in a root script

I would like to know if it's possible to exectute certain lines of this script (or all the script) as normal user

Yes, it's possible—and a good idea.

Python's os module has a group of functions to set the real, effective, and saved user and group id, starting with setegid. What exactly each of these does is up to your platform, as far as Python is concerned; it's just calling the C functions of the same names.

But POSIX defines what those functions do. See setuid and seteuid for details, but the short version is:

• If you want to switch to a normal user and then switch back, use either seteuid or setreuid, to set just effective, or real and effective, but not saved UID. Then use the same function again to set them back to root.
• If you want to run the whole script as a normal user and make sure you can't get root back, use setresuid instead, to set all three.

If you're using Python 3.1 and earlier, you don't have all of these functions. You can still use seteuid to switch effective ID back and forth, but setuid will… well, it depends on your platform, but I think most modern platforms will change saved as well as real, meaning you can't get root back. If you read the linked POSIX doc, there are a bunch of caveats and complexities in the POSIX documentation. If you only care about one platform, you probably want to read your local manpages instead, rather than reading about all of the cases and then trying to figure out which one covers your platform.

So ,do you know if it's possible to change it, with a subprocess, or other?

That isn't necessary (at least on a conforming POSIX system), but it can make things easier or safer. You can use subprocess, multiprocessing, os.fork, or any other mechanism to launch a child process, which immediately uses setuid to drop privileges—or even setresuid to give up the ability to ever restore its privilege. When that child process is done with its task, it just exits.

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