How can you view environment variables inside a running Docker container?

To view environment variables inside a running Docker container, you can execute the docker exec command, which runs a command inside the container. For example:

docker exec <container_id_or_name> printenv

This command will display all environment variables. You can also use:

docker exec <container_id_or_name> env

If you want to see a specific variable, such as PATH:

docker exec <container_id_or_name> printenv PATH

Alternatively, you can access the container with an interactive shell:

docker exec -it <container_id_or_name> /bin/sh

or

docker exec -it <container_id_or_name> /bin/bash

and then use the env or printenv command inside the container.