Forward Bytes from Serial Port over IP using C/C++ on OpenWRT Linux

Question

I am receiving packets of 35 Bytes on my Serial Port and would simply like to forward/tunnel them via Ethernet. I was wondering if anyone had any useful codesnippets. I know this can be done using netcat, but I was hoping for a simple C/C++ Program to be run as a background process. I am running a OpenWrt Linux with very limited Flash. Thanks in advance!

Answer 1

You can make a small program, that opens the serial port for reading and a socket for the outgoing communication.

In a loop, read from the serial port, and what you read you write to the socket.

In pseudo-ish code:

int ser = open("/dev/ttyS0");
int sock = socket_connect();

for (;;)
{
    ssize_t r = read(ser, data, MAXLEN);
    if (r > 0)
        write(sock, data, r);
}