Can you give an example of each?

Certainly! Here are examples demonstrating the use of $0 and $BASH_SOURCE in a Bash script.

Example of $0

Create a script named example0.sh:

#!/bin/bash
echo "The name of this script is: $0"

When you run this script from the command line:

./example0.sh

The output will be:

The name of this script is: ./example0.sh

Example of $BASH_SOURCE

Create two scripts: main.sh and helper.sh.

helper.sh:

#!/bin/bash
echo "This script is: ${BASH_SOURCE[0]}"

main.sh:

#!/bin/bash
source ./helper.sh

When you run main.sh from the command line:

./main.sh

The output will be:

This script is: ./helper.sh

In this example, $BASH_SOURCE[0] in helper.sh gives the name of the script that is currently being executed, which is helper.sh, even though it was called from main.sh.