串口数据通过/ dev / ttyS0和文件读/写

I recently picked up a serial cable with crossover adapter (Null Modem) and thought it might make an educational experiment to see if I could do some controlled passing and receiving of bytes over it between two Linux (Lubuntu) computers. I have written some rudimentary code in Java that opens the /dev/ttyS0 "file" as input and output file streams. I recently picked up a serial cable with crosso