$ skopeo inspect -n docker://quay.io/fedora/fedora:39 | jq .Env [ "DISTTAG=f39container", "FGC=f39", "container=oci" ] $ skopeo inspect -n docker://quay.io/fedora/fedora:40 | jq .Env null $ Also $ skopeo inspect -n docker://registry.access.redhat.com/ubi9/ubi:latest | jq .Env [ "PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin", "container=oci" ]
Specifically, there's a fair amount of tooling that checks for `container` being set.
I guess this is somewhat bike-sheddable as uptake of that environment variable hasn't been high. Oh wait...interesting. There's another wrinkle here, which is I think podman itself will auto-set the variable if it hasn't been set, but other container runtimes (e.g. at least cri-o as used by OCP) doesn't inherit this behavior. And I think docker never did either. Well...I guess arguably we could try to change everything to do the stanza of "check /run/.containerenv, check /.dockerenv". But that's going to take some time to propagate with a pretty wide potential blast radius: https://github.com/search?q=getenv%28%22container%22%29&type=code
Opened https://pagure.io/fedora-kiwi-descriptions/pull-request/51 and https://pagure.io/fedora-kiwi-descriptions/pull-request/52
This is now fixed [cverna@laptop] $ skopeo inspect -n docker://quay.io/fedora/fedora:rawhide | jq .Env [ "container=oci" ] ~ [cverna@laptop] $ skopeo inspect -n docker://quay.io/fedora/fedora:40 | jq .Env [ "container=oci" ]