br_multicast...ter_adjacent(9)

🦋 br_multicast_has_router_adjacent — the kernel API manual, bestie edition 🦋

okay so this is a page from the Kernel API Manual and honestly? it's a lil cutie. let's get into it 💅

---

✨ NAME ✨

br_multicast_has_router_adjacent — literally checks if there's a router chillin' behind a bridge port 🫶

---

🌸 SYNOPSIS 🌸

bool br_multicast_has_router_adjacent (struct net_device *dev , int proto );

that's it. that's the whole vibe. returns a bool and everything 🎀

---

💖 ARGUMENTS 💖

• dev — the bridge port that you're checking adjacent to for a multicast router. like, this is your main character interface ✨
• proto — the protocol family you wanna check for, and the mapping is lowkey iconic: IGMP -> ETH_P_IP, and MLD -> ETH_P_IPV6 👑

---

🔥 DESCRIPTION 🔥

so what it does: it checks whether the interface you handed it has a bridge on top of it, and if it does, it returns true when a multicast router is sitting behind one of the other ports of that bridge.

and if not? false. no cap, that's the whole deal 🙈

---

🧚 SEE ALSO 🧚

• the kernel file ./net/bridge/br_multicast.c (yes, that's where the magic lives 💜)
• br_multicast_list_adjacent(9)
• br_multicast_has_querier_anywhere(9)
• br_multicast_has_querier_adjacent(9)

go read those next, bestie, they're giving sequel energy 🌈

---

and that's the whole page!! mwah 💋 this one came from ./net/bridge, dated October 2026, and the title up top is br_multicast...ter_adjacent(9) — slay, go check for those routers 🎀✨💅