How to export environment variable to background process run using sudo?

Question

I have a bash script env_setter.sh. It sets an environment variable. It contains:

#!/bin/bash
echo "inside env_setter script....."
export NAME="jake"

I have another script tester.sh. It tries to print the value of the environment variable set by env_setter.sh. It contains:

#!/bin/bash
echo "Inside tester script..."
echo "$NAME"

Then I have a script runner.sh that executes both of the above scripts as follow:

#!/bin/bash
echo "Inside runner script..."
. ./env_setter.sh
echo "$NAME"
sudo nohup ./tester.sh > demo.log 2>&1 & echo $! > save_pid.pid

Now when I run runner.sh, I get following output in demo.log:

inside env_setter script.....
jake
Inside tester script...

As we can see, the last echo command in tester.sh doesn't print anything. This is because the environment variable that we set with env_setter.sh is not being exported inside the context of tester.sh.

So, how do I export the environment variable to the background process in such cases?

Answer 1

Normally sudo replaces the current environment with the environment of the new user, for security reasons. Use sudo -E to preserve the calling environment. Or you can pass variables on the command line, sudo NAME=jake.