Bind mounts vs. Volumes in Docker Compose

https://docs.docker.com/storage/bind-mounts/#choose-the–v-or—mount-flag

Using simple volume mounts creates a directory if the file does not exist, e.g.

docker run \
  --rm -it \
  --user $(id -u):$(id -g) \
  -v /tmp/foo.cfg:/tmp/foo.cfg \
  debian:bullseye true

stat /tmp/foo.cfg
rm /tmp/foo.cfg

Using the --mount flag does not, e.g.:

docker run \
  --rm -it \
  --user $(id -u):$(id -g) \
  --mount source=/tmp/foo.cfg,destination=/tmp/foo.cfg \
  debian:bullseye true

# errors out, as it should be

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https://docs.docker.com/compose/compose-file/compose-file-v3/#long-syntax-3

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