Does that work? I've never seen it used. It seems easy to escape.

The docs seem to suggest using alternate approaches.

> Modern systems provide more secure ways to implement a restricted environment, such as jails, zones, or containers.

https://www.gnu.org/software/bash/manual/html_node/The-Restr...

I don't think I've ever seen it used. I think the idea was back in the day when you wanted to let a user have a shell login (because that's the only way you could use a shared computer) but wanted to confine them to a specific directory and prevent them running anything that wasn't in the pre-defined PATH that you set for them.