is_link_local_ether_addr(9)

📦 version 7.3.1, in nixpkgs unstable

okay so this is a page from the Kernel API Manual, and honestly? it's a little cutie. we're checking whether an Ethernet address is link-local. that's the whole vibe. let's get into it 💅

🌸 NAME 🌸

is_link_local_ether_addr — figure out if the Ethernet address someone handed you is link-local or not 🦋

✨ SYNOPSIS ✨

bool is_link_local_ether_addr (const u8 *addr );

like, you give it a pointer, you get a bool back. that's it. that's the whole function. iconic behavior honestly 👑

🎀 ARGUMENTS 🎀

  • addr — a pointer to a six-byte array holding the Ethernet address 💖 six bytes. count 'em. not five, not seven.

💜 RETURN 💜

it hands back true if the address is a link local reserved addr (01:80:c2:00:00:0X) per IEEE 802.1Q 8.6.3 Frame filtering 🌈

not me memorizing that hex pattern… 01:80:c2:00:00:0X bestie, write it down ✍️

🦋 DESCRIPTION 🦋

⚠️ please note: addr must be aligned to u16. this is not a suggestion, this is a rule, do not come for me 😭

that's genuinely the whole description. short and sweet. main character energy, minimal words 🎀

🔥 SEE ALSO 🔥

the kernel file is ./include/linux/etherdevice.h and it's got a whole friend group, fr fr. go say hi to all of them 🫶

and that's the page!! 💖 this one lives in ./include/linux, dated October 2026, and it's part of the Kernel API Manual — slay, go read your ethernet headers bestie, ily, bye 🎀✨

📦 where this page comes from