Hi Klemens, Re: IIRC, we simply did the equivalent of "cat space.oct" or "cat pong.oct". (It was from MPE, so it was probably: FCOPY FROM=space.oct;to= ) I noticed in your README you mentioned overflowing the terminal at serial speeds ... that's solved by using enq/ack pacing, a strap you can enable on HP terminals (also called "flow control"). It's been awhile since I've used it, but I found a writeup here: http://docs2.attachmate.com/verastream/vhi/7.1/en/index.jsp?topic=%2Fcom.at… And, from Robelle's website at http://www.robelle.com/smugbook/network.html we see: ENQ/ACK is a proprietary method of flow control used on Classic MPE V systems and is still built-in to most HP terminals and enabled by default. The transmitter sends an ENQ (Enquiry, decimal 5, Control-E) every 80 characters (or so). When the receiver is ready for more data, it replies with an ACK (Acknowledge, decimal 6, Control-F). If there is no reply in 10 seconds, MPE V resumes printing printing (Term Type 10). If you disable ENQ/ACK on your terminal, you will see output interspersed with pauses. MPE/iX and HP-UX normally use XON/XOFF Flow Control instead of ENQ/ACK. So...you could have a little C program that loops: while data left > 0 if >= 80 bytes then write 80 bytes of data write an ENQ (decimal 5) read, waiting for an ACK (decimal 6) (preferably with a timeout of a second or two, in case ENQ/ACK isn't enabled on the terminal) else write remaining data Stan