I am successfully using SER2NET on a Raspberry Pi to translate RS-232 data to Ethernet. But I would like to "watch" the data coming from the serial port for a certain string, and if there is a match, I would like to send a "control string" back out the RS-232 port. It doesn't matter if the Ethernet port "sees" this returned string or not.
I'm running at 115K baud and the RPi is doing a lot of other things simultaneously, so whatever approach I use cannot use a lot of processor time. Does anyone know of a good way to do this?