A colleague asked how he might use a relative path e.g. ~/foobar or ../foobar instead of an absolute path e.g. /home/Dave or /tmp/foobar when mapping a path on the host to a path inside a container, using Docker for Mac.
Well, I had a play ....
For reference, Docker uses a concept known as bind mounting as evidenced by docker run --help
-v, --volume list Bind mount a volume