and on reflection how about something more like:

``
      -H=[unix:///var/run/docker.sock]: tcp://[host[:port]] to bind/connect to or unix://[/path/to/socket] to use. When host=[0.0.0.0], port=[4243] or path=[/var/run/docker.sock] is omitted, default values are used.
``

we use the ``tcp://[host[:port]]`` syntax in places to show optional parameters, so thats consistent - I'm not hyper-enthused by the ``port=[4243]`` syntax as it conflates with how we specify actual parameters - but the crux is to tell the user what the values are, not to force them to hunt for them :)

oh - and can i do ``-h udp://``?