Thank you! Seems I have the complete kernel, but the little add-ons that make life bit easier aren't always included. Luckily I have some cool libraries, such as SDL. I've found a neat way to check whether a network cable is plugged in and active, by running command line function "ethtool eth0" and piping output to text file, which I then parse. Gives me the "link detected: yes/no" answer I was looking for
And for sure, I found that information in an online networking manual which starts with the absolute basics - brilliant! Even though I'm working on Linux, I have to do some embedded stuff on a very basic level. It's fun, but stressful when I can't find the exact thing I'm looking for. But what a sense of achievement when I get the firmware to do exactly what I want
Anyhow, the struggle continues. Some lovely equipment has decided it wants 2-byte parameters to be swopped around (first high-order byte, then low-order byte) before it accepts it. Not the whole package, just any incidental 2-byte parameters. What fun. NOT!
Thanks for the encouragement