As root, how do I read another user's environment variables?

I have a script that should be run using sudo, with the goal of "promoting" a script from a user-level installation to a system installation. Reproduced here:

#!/bin/bash

if [[ $EUID -gt 0 ]]; then
    echo "This script must run as root"
    exit 1
fi
if [[ -z "${SUDO_USER-}" ]]; then 
    echo "Sudo user not found"
    exit 1
fi
if [[ -z "${1-}" ]]; then
    echo "Usage: sudo share-command SCRIPTNAME"
    exit 1
fi
user_bin="$(getent passwd $SUDO_USER | cut -d: -f6)/.local/bin"
src="$user_bin/$1"
dst="/usr/local/bin/$1"
if [[ -f "$dst" ]]; then
    echo "Already exists"
    exit 1
fi
/usr/bin/install -m 755 "$src" "$dst"

Currently, it looks up the sudo user's home directory and looks in .local/bin relative to that.

I would like it to be able to find the script being installed by name.

I do not want to set the root user's PATH; I understand that this is insecure and there are protections against it. But given that the script is running as root, and I know who the sudo user is, it seems like I should be able to determine that user's PATH, and then iterate over it manually to look for the script.

Is this indeed possible? How?

posted about 17 hours ago

CC BY-SA 4.0

Karl Knechtel‭

631 reputation 29 11 102 15