Thought I’d share this here, since it might help others (feedback welcome):
--volumes-from to remount the volumes for the Codespace (e.g.
/workspaces/myrepo) inside the container you are starting. This requires knowing the container ID of the container in which the Codespace is running, which we can obtain with
docker ps --filter "label=Type=codespaces".
As a bonus
--workdir can also be used to start the container in the current directory.
Putting it together:
$ docker run -it --rm --volumes-from $(docker ps --filter "label=Type=codespaces" -q) --workdir $(pwd) alpine:latest /workspaces/myrepo/ # ls . [list of files]