how to become root within a script

Hello, i want to run a script as a regular user, and in that script, automatically become root so that the script can execute a command.

I'm using DSL Linux.

I tried putting sudo and sudo su before the script, but that didn't work.
This is an automated script, so i don't have the luxury of just typing in sudo root_only_script.sh from a bash window.

This is the idea:

#!/bin/bash
((become root))
root_only_script.sh
exit

The reason for this is because i have a samba share setup on the server but when files are moved to the share from windows computers, they require root permission in order to be changed. So i want to have a script that can change those permissions via a chmod 0777 -R /home/dsl/

The samba share is a no password, guests ok share. If there is a better solution than becoming root, that is welcome too.

-Thanks for the help

You need to use sudo with the nopasswd option, since you don't want sudo to prompt for a password. In addition, you need sudo configured to allow use without a tty (a script).

Run visudo, and make sure the following statement has the exclamation point:

Defaults !requiretty

That will now allow sudo from a script.

Add an entry that will allow the script to be executed by the user. For example:

someuser somehost = NOPASSWD: /usr/local/bin/somescript

I think the way to do it would be to edit the sudoer file to add the username you will use, and the command to run from sudo.

Then, in the script, 'sudo <command>'.

In the sudoer file, <username> /path/to/root_only_script.sh

In the script, sudo /path/to/root_only_script.sh

I don't do such things, so I'm just guessing.

You don't want to directly edit the sudoers file. The reason is that sudo is very picky - The slightest syntax error will prevent all sudos from working. The visudo command runs a syntax check before changing the file, to prevent such an error.

If you have access to this samba server, you could call your script as a root cron job. Then the script will be running as root anyway. You will need to make sure that your script doesn't print our expect input, so you may need to add redirection to /dev/null for each command.