How to undo "sudo -s" in OSX terminal? - macos

I ran sudo -s in the OSX terminal and now it is defaulted to running as root.
Is there a way to undo this?

On Unix Type operating systems, all you have to do is type in the exit command this should exit root and return to the user you were currently running under before entering the command.
You can also hit Command+D and that should return you to the user you were running as before the command as well.

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Shutdown or Reboot a WSL session from inside the WSL session

I would like to be able to reboot WSL sessions. To do so is a little awkward as WSL does not use systemd so we cannot use reboot. Within a WSL session, we can run any Windows executable:
boss#Asus: ~ $ wsl.exe -l -v
NAME STATE VERSION
* Ubuntu-20.04 Running 2
fedoraremix Stopped 1
Alpine Stopped 1
Ubuntu Stopped 1
Therefore, we can use wsl.exe (you have to make sure to always add .exe when calling Windows commands or they will not work) to shutdown the currently running WSL session wsl.exe -t Ubuntu-20.03, but the problem is that I don't know the session name.
When we are inside a WSL session, hostname is something different, and so I don't know how to find the name of the currently running session that I am inside (maybe a Windows process command that tells me what process I am running from??).
Ideally, I would like a command to equate to a reboot. I guess this would have to look something like:
Run an asynchronous command that will initiate a new session 5-10 seconds in the future to allow the previous session to fully shutdown (and that will not terminate when this session is terminated).
Terminate the currently running session with wsl.exe -t <my found name>.
A few seconds later, the new session will start up.
Credits to the commenters above.
To shutdown a session from within a WSL guest, you can run:
wsl.exe --terminate $WSL_DISTRO_NAME
Rebooting is also possible, however so far I do not know how to get a new terminal inside the same console window. The following will reboot the WSL guest and open a new console window of it when it has finished:
cd /mnt/c/ && cmd.exe /c start "rebooting WSL" cmd /c "timeout 5 && wsl -d $WSL_DISTRO_NAME" && wsl.exe --terminate $WSL_DISTRO_NAME
Explanation:
From the perspective of Windows, WSL systems are mounted as network resources. cmd does not support the resulting UNC path formats such as \\wsl$\Debian\<...>. Therefore it may be best to cd to a directory it can resolve as a Windows path instead, such as C:\, before it is executed. If ommited, cmd will complain and change its directory to cmd's %windir%.
&& runs another command after the previous one has finished in linux and windows cmd.
cmd.exe /c starts a cmd instance and tells it to execute a command that follows.
start "<WindowTitle>" ... is a cmd-internal command to run another program inside its own window, independent of the cmd instance. In this case the program is another cmd window. It will not be affected when WSL shuts down.
In the original Linux-Terminal, the first cmd /c command has finished, and the third command after && shuts down the guest like above.
The second cmd window waits for a few seconds, then starts a new WSL session of the same WSL machine.
Creating an Alias
You can make this easier to use by creating an alias. For bash users, edit your ~/.bashrc file and apply the changes afterwards:
nano ~/.bashrc && source ~/.bashrc
Add either or both of the lines below anywhere in the file.
You can of course choose any name you want. Both shutdown and reboot exist as systemd commands, but since they do not work in WSL machines, you can replace them with an alias as follows:
alias shutdown='wsl.exe --terminate $WSL_DISTRO_NAME'
alias reboot='cd /mnt/c/ && cmd.exe /c start "rebooting WSL" cmd /c "timeout 5 && wsl -d $WSL_DISTRO_NAME" && wsl.exe --terminate $WSL_DISTRO_NAME'
Expanding on the ansver from #BasementScience
To manage a remote WSL I've set up a Windows TaskScheduler job to start wsl with an /etc/init-wsl which in turn starts cron, ssh, rsyslog and autossh (so I can connect back to WSL).
So naturally I'm keen to get these processes started also on a remote WSL reboot, so I'm able to login again afterwards.
# Added to $HOME/.bashrc - Renamed aliases to separate from OS commands
alias wslshutdown='wsl.exe --terminate $WSL_DISTRO_NAME'
alias wslreboot='cd /mnt/c/ && cmd.exe /c start "Rebooting WSL" cmd /c "timeout 5 && wsl -d $WSL_DISTRO_NAME" -- sudo /etc/init-wsl && wsl.exe --terminate $WSL_DISTRO_NAME'
The detail is here ... & wsl -d $WSL_DISTRO_NAME" -- sudo /etc/init-wsl & ...
This will not start a new shell, but will start my processes so I can login again.
The /etc/init-wsl script have to be created:
sudo touch /etc/init-wsl && sudo chmod 755 /etc/init-wsl
# Add services as needed
sudo bash -c 'cat << EOF > /etc/init-wsl
service ssh start
service cron start
EOF'
# Ensure your user (the %sudo group) can sudo the init script without password
sudo bash -c 'cat << EOF > /etc/sudoers.d/user-service
%sudo ALL=NOPASSWD: /usr/sbin/service *
%sudo ALL=NOPASSWD: /etc/init-wsl
EOF'

Change default terminal shell to root

I was experimenting with my root user on macOS, and performing a zsh installation for the root user and now I can not access my root user. When wanting to enter the school
sudo su
The console returns the following message, and I do not know how to fix this problem.
"su: /usr/bin/zsh: No such file or directory"
The error message tells you, that for the user root the default shell is configured to be /usr/bin/zsh and su is trying to start this programm, but it is not there.
You can do a
sudo /bin/bash
to get a root shell and fix your problem. Either copy your zsh to the right location or change the shell for root back to the default. on my mac it is "/bin/sh"
If you don't have zsh installed on mac, try this:
brew install zsh

How do I run a shell script with administrator privileges through AppleScript without prompting for a password?

I want to have my AppleScript application run a Python script with sudo, but I don't want the application to prompt the user for a password (our users do not have sudo privileges).
The Python script has been added to the /etc/sudoers file appropriately (ALL ALL=NOPASSWD: /path/to/script.py). In the terminal, I can do (as a regular, non-privileged user):
$ sudo ./script.py
and it runs perfectly well. But in AppleScript when you try to do:
do shell script "sudo ./script.py"
You of course get the "sudo: no tty present and no askpass program specified" error. But if you change it to:
do shell script "./script.py" with administrator privileges
AppleScript insists on presenting a popup window to ask for the password. I have also tried passing a null password to sudo with a pipe:
do shell script "echo '' | sudo -S ./script.py"
but that also does not work. (I think it tries to run sudo individually first and then pass the command through, which won't work because the user doesn't have sudo privileges!)
I need a solution where AppleScript will run the Python script with sudo. I would prefer the script stays unreadable and un-executable by average users for security reasons, and is only executed through the AppleScript. (I know that, hypothetically, the users could call sudo script.py and it would run, but that's assuming they even know about sudoers; I'm trying to keep it as secure as possible while still usable).
I'm still pretty new to AppleScript, so any help would be greatly appreciated! Thanks!
When I added ALL ALL=NOPASSWD: /Users/myusername/a to sudoers and ran echo $'#!/bin/bash\nsay $(ls ~root|head -n1)'>~/a;chmod +x ~/a, do shell script "sudo ~/a" ran the script as root without requiring a password.
I'm guessing the problem is that you specified the path like do shell script "sudo ./script.py". Try to use do shell script "sudo ~/script.py" instead. The default working directory is for do shell script is / and not ~/.

How to create an Apple Script that runs a Terminal command?

I want to create an apple script that opens terminal and summons this command : sudo killall coreaudiod
How is this possible?
do shell script "sudo killall coreaudiod" with administrator privileges
the user gets asked for the password then

sudo being backgrounded not the command

I have the following in my ~/.profile file...
alias mysqlstart='sudo /opt/local/bin/mysqld_safe5 &'
However, when I type $ mysqlstart. I'm not asked for my password and mysql doesn't start.
When I foreground the job, it's stuck on asking for my password.
Is there a way of setting the alias so the /opt/local/bin/mysqld_safe5 is backgrounded not sudo?
This is my shell's version information:
GNU bash, version 4.2.37(2)-release (i386-apple-darwin11.3.0)
From the sudo man page:
The -b (background) option tells sudo to run the given command in the
background. Note that if you use the -b option you cannot use shell
job
control to manipulate the process. Most interactive commands will fail
to work properly in background mode.
I wasn't aware of the sudo -b option, which sounds like the better solution.
I have used something like the following before, which I suppose has the advantage that it allows for job control by the shell:
alias mysqlstart='sudo true; sudo /opt/local/bin/mysqld_safe5 &'
The first command sudo true should prompt you for your password while not really doing anything, but allows the second sudo to execute without prompting for your password.

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