Identify user in a Bash script called by sudo

Question

If I create the script /root/bin/whoami.sh containing:

#!/bin/bash
whoami

and this script is called by a user with a properly

Answer 1

Using whoami, who am i, who, id or $SUDO_USER isn't right here.

Actually, who is never a solution to the question, as it will only list the logged in users, which might be dozens...

In my eyes, the only valuable answer is the use of logname.

Hope this helps

Rob

Answer 2

If it's the UID you're looking for (useful for docker shenanigans), then this works:

LOCAL_USER_ID=$(id -u $(logname))

Answer 3

Here is how to get the username of the person who called the script no matter if sudo or not:

if [ $SUDO_USER ]; then user=$SUDO_USER; else user=`whoami`; fi

or a shorter version

[ $SUDO_USER ] && user=$SUDO_USER || user=`whoami`

Answer 4

I think $SUDO_USER is valid.

#!/bin/bash
echo $SUDO_USER
whoami

Answer 5

who am i | awk '{print $1}' didn't work for me but who|awk '{print $1}' will serve the job

Answer 6

$SUDO_USER doesn't work if you are using sudo su -.
It also requires multiple checks - if $USER == 'root' then get $SUDO_USER.

Instead of the command whoami use who am i. This runs the who command filtered for the current session. It gives you more info than you need. So, do this to get just the user:

who am i | awk '{print $1}'

Alternatively (and simpler) you can use logname. It does the same thing as the above statement.

This gives you the username that logged in to the session.

These work regardless of sudo or sudo su [whatever]. It also works regardless of how many times su and sudo are called.