Question

I’m trying to write a bash script that sets up my web development environment in ubuntu. As part of the process of setting up the script, it needs to edit files that are owned by root. It also needs to create fields in the public_html directory of the user that runs the script.

Should I therefore require that the script be run as the superuser? If it should, then how do I get it to access the current user’s username? I would normally use the $USER variable, but I can’t do that if the script is being run as the superuser. If I’m not the superuser, how can I get the script to request super user privileges for certain operations, while not requiring the user to type in a password for every operation that requires super user privileges.

Thanks

Answer 1

You can use the -E flag for sudo to preserve the environment variables, or, you can set up sudoers to preserve the environment on a per-command basis.

You can also set up the sudoers file to not ask for a password on a per-command basis, for example, to allow user xy to use smbmount without asking for a password:

xy ALL=NOPASSWD: /usr/bin/smbmount

In your case, it would be enough to just store the current user in a variable before invoking sudo, and use the already saved username:

CURRENT_USER=$USER

sudo yourscript.sh $CURRENT_USER

Then read the username from $1.
You can also use the SUDO_USER env variable, which is set to the user who is invoking sudo.