External containers are containers created outside of Podman.
For example Buildah and CRI-O Containers.
$ buildah from alpine
alpine-working-container
$ buildah run alpine-working-container touch /test
$ podman container exists --external alpine-working-container
$ podman container diff alpine-working-container
C /etc
A /test
Added --external flag to refer to external containers, rather then --storage.
Added --external for podman container exists and modified podman ps to use
--external rather then --storage. It was felt that --storage would confuse
the user into thinking about changing the storage driver or options.
--storage is still supported through the use of aliases.
Finally podman contianer diff, does not require the --external flag, since it
there is little change of users making the mistake, and would just be a pain
for the user to remember the flag.
podman container exists --external is required because it could fool scripts
that rely on the existance of a Podman container, and there is a potential
for a partial deletion of a container, which could mess up existing users.
Signed-off-by: Daniel J Walsh <dwalsh@redhat.com>
db23e12611