Import config files via command line - Satellite 5.6

Does anyone know how to import config files from client machines using the command line? On the Satellite 5.6 web interface, it is simple...

configuration->Add files->Import Files

Then simply type in the path of the file that you want to import and click "Import Configuration Files", then confirm. Once rhn_check runs on the target machine, the file gets uploaded to the Sandbox area, from where you can download them.

There is absolutely no mention of this function in the command line references that I have seen. I've tried using

$ spacecmd system_addconfigfile

But that has the functionality of...

Configuration->Add Files->Upload File

...which is not what I want. I want to be able to retrieve a file that has been generated on a server and upload it to Satellite. I then want to download it from the Sandbox are and place it in a directory of my choosing. I want to do all this via the command line.

If anyone can help by providing information on...
1. How to import a file by command line
2. How to download that file from Sandbox into the filesystem

...then I would be most grateful

Many thanks