Get separate output for stdout/stderr on "run"

[sreuter]

I'm looking into ways to get demuxed log output (stdout/stderr) for a "run" call.

As docker.run() takes a destination stream for logging, it may be possible to provide an instance of container.modem.demuxStream(), which get feed by separate streams for stdout/stderr beforehand. While achieving this from the outside might be possible for the user, it would be far from convenient in practice. See example

From my point of view, two options should be added to the "run" functionality

• Allow providing two separate destinations streams for stdout/stderr
• Allow user to get buffered version of different logout outputs