This creates a container by copying the corresponding files
from the layers into the containers. This is not gonna be very useful
on a developer setup, as there is no copy-on-write or general diskspace
sharing. It also makes container instantiation slower.
However, it may be useful in deployment where we don't always have a lot
of containers running (long-running daemons) and where we don't
do a lot of docker commits.
lxc-start requires / to be mounted private, otherwise the changes
it does inside the container (both mounts and unmounts) will propagate
out to the host.
We work around this by starting up lxc-start in its own namespace where
we set / to rprivate.
Unfortunately go can't really execute any code between clone and exec,
so we can't do this in a nice way. Instead we have a horrible hack that
use the unshare command, the shell and the mount command...
There are a few changes:
* Callers can specify if they want recursive behaviour or not
* All file listings to tar are sent on stdin, to handle long lists better
* We can pass in a list of filenames which will be created as empty
files in the tarball
This is exactly what we want for the creation of layer tarballs given
a container fs, a set of files to add and a set of whiteout files to create.
To do diffing we just compare file metadata, so this relies
on things like size and mtime/ctime to catch any changes.
Its *possible* to trick this by updating a file without
changing the size and setting back the mtime/ctime, but
that seems pretty unlikely to happen in reality, and lets
us avoid comparing the actual file data.
add AutoRemove to HostConfig
add -rm flag to docker run
add TestRunAutoRemove to test -rm
docs: add -rm to commandline/command/run
add hostConfig to container monitor
make monitor destroy the container via -rm
This adds support for automatically removing a container after it
exits. The removal of the container is handled on the server side.
We never want the container to be in the same process group as the
daemon, as then the container will receive signals sent to the
process group of the container.
