saltstack/salt — pull request #12038 by ticosax (2014-04-16 15:36:03+00:00)
Title: Since docker is using multiple driver extend its attach support.

Add support for attaching processes to a container driven by `libcontainer`.
`lxc` is still supported.

reference implementation http://jpetazzo.github.io/2014/03/23/lxc-attach-nsinit-nsenter-docker-0-9/