Python Telnet and \xff = 🤮
After trying to make node.js do what I think node.js is not meant to do (or I just don’t want to sink more time to figure how to make it do what I really think it’s not meant to do)*, I decided maybe I’d try Python. This relates to yesterday’s Promise Chain Pain.
As usual, that was a mistake.
I decided to send a self-test line to one of the Ohio River Bridge Counters, which is a hex line of ‘ff aa c0 02 00 02 00 02’. However, as I watched in WireShark, it was sending ‘ff ff aa c0 00 02 00 02’. The extra ‘ff’ at the beginning is a problem.
This is what my computer is sending
So I looked at the documentation, which led to the source code.
WTF?
Apparently, any “IAC” characters are doubled.
OhFFS
Apparently, char(255) is “IAC”, and the hex character ‘ff’ is 255.
Yeah, \xff = 255. We already knew that, I just wanted to prove it.
Back to the drawing board…
Update: I’m probably being a little mean to Python. It’s the language I love to hate. I CAN use the socket package to work with these counters, so I might be good. Might.
That’s how I mostly feel about Python. Tie it to a stick to keep it out of the way for a while.
‘* = I’m not trying to rip on Node.js here. While there’s some things that baffle me with it (like the lack of errors for forgetting semicolons and the few occasions where I looked back at something and wonder how it ever worked), I have been enjoying Node.js and will likely be using it more.
