Set up a hardware and software protocol for communicating between two computers using their parallel ports. Use the disscusion on pages 941-942 of Messmer as a guideline.

1. Decide on a handshaking protocol.
2. Wire a cable to implement your protocol.
3. Write a program to transmit and receive data over the parallel port.

1. If a filename is specified on the command line, send that file to the other computer.
2. If no filename is specified, send anything from the standard input to the other computer.
3. Use interrupts to receive anything sent from the other computer.