Interprocess communication with rhino

Is there a good way for external processes to issue commands to and/or read data from an active Rhino process? I’m not trying to do anything sophisticated, and if creating a “communication” plugin to talk to is called for, that’s totally on the table. I’m told you can do this using COM and RhinoScript, but I’d like to avoid COM if at all possible, because, well, it’s COM.

See the RhinoFromCSharp sample at the bottom of this page

So COM is the way to do this? I guess I should have specified this was for Rhino 5, but I found

That is the easiest approach. Interprocess communication is a pretty broad topic, but this is the easiest way to launch and control Rhino from an external process.