While I agree with the feature request, I’ll again (like in a few previous feature requests) say that I think that it would be unwise to implement something like system level interaction, which this – in one way or another – requires – without a good permission system (since it’s very easy to install plugins with the plugin manager and potential malware could damage the opinion about plugins in XD a lot).
You can find a great discussion about security concerns which also affect this request at Run External Application from XD Plugin…
For basic communication (although I do understand that that isn’t as easy to use in C++), you can always use the WebSocket API as long as your application is already running (which would mean communication is possible – opening that app if it isn’t running is then a whole different issue and handled in the request I’ve linked to above).