Pcb-rnd comes with a interpreter which is known as the batch ui. This batch UI is a default buildin and can be summond at any time when running pcb-rnd (see code below). Batch mode will compile and run as the default user interface when pcb-rnd is compiled on systems without any gui libs installed. The batch UI is useful for automation, test, and debugging.
./pcb-rnd --gui batch
Uses and examples for Batch mode