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Refined Printing Command Stream, also known as RPCS, is a vector-based[1] printing/duplicating control protocol, designed for communication between Microsoft Windows PC clients, and several lines of Ricoh copiers. Drivers provided by Ricoh install the chosen copier to behave as a printer device.
The size-efficiency of the protocol is comparable to PCL6.[1]
Ricoh offers RPCS based drivers for Windows, Mac OS and to some extent for Linux.
Drivers for Linux are provided only on the Japanese website. Instead of Aficio they are called IPSiO.[2][3]