[coldstartops]

also they use mDNS, which many programming languages, such as go, got it in their net library

[klabb3]

No they don’t? There are several 3p libs for it but not in std. Unless I’m blind and didn’t get the memo.

[coldstartops]

No you didn't miss. I mixed the concept, UDP broadcast similar to mDNS, yes part of net library. actual mDNS like visible in Finder and actual RFC implementation not part of standard library. What I was trying to say was easy to make "mdns-ish" with just standard lib, rush typed it and ended up like that.

[klabb3]

Yeah I implemented my own in Go because I was unhappy with the 3p ones, so that’s why I reacted. It’s surprisingly hard to get right, in particular:

1. Backoff and timer logic to not flood network.

2. Caching entries for the same reason.

3. Handling multiple network interfaces, and detecting when they changed.

[coldstartops]

hah, I feel you for 3. I was constantly hitting the loopback network interface and I was like, why no discovery. in hindisght bad idea to always get the first entry in an array, now go through a list of network interfaces that i spam.

for 1. i send a mutlicast of max 512 bytes on 224.0.0.167:26999 every 3 seconds 2. not really caching, just have a map of people that get discovered.

and god bless, I just rolled with this. if people will use the tool and they will complain about it, then it will be a problem for later. for me between my home devices did not notice inconveniences.

in total around 200 lines of golang.