i40e_dcbnl_setnumtcs(9)

📦 version 7.3.1, in nixpkgs unstable

💅 i40e_dcbnl_setnumtcs — a Kernel API Manual moment 👑

okay so bestie, we're in the kernel API manual (man 9 territory, yes it's giving big-brain energy), and today's main character is i40e_dcbnl_setnumtcs. buckle up 🎀

✨ NAME ✨

i40e_dcbnl_setnumtcs — set CEE number of traffic classes 🌸

🦋 SYNOPSIS 🦋

int i40e_dcbnl_setnumtcs (struct net_device *netdev , int tcid , u8 num );

that's the whole vibe. one function, three args, returns an int. slay. ✨

🍓 ARGUMENTS 🍓

  • netdev — the corresponding netdev, aka the network device we're talking about 🫶
  • tcid — the TC id, like the traffic class's little name tag 💜
  • num — total number of TCs, a u8, so keep it small-ish bestie 🙈

💀 DESCRIPTION 💀

So the intent here is to set the total number of TCs (traffic classes). iconic concept, love that for us.

But — and I cannot stress this enough — the manpage literally says “(Unsupported)” 😭. Not me finding out the function's whole job description comes with an asterisk. So like, it's setnumtcs... but it's unsupported. that's the entire tea. no notes. ⭐

👑 real talk: nothing here promises it actually sets anything. the manual says unsupported, so treat it as unsupported. don't come for me, I'm just the messenger 💅

🌈 SEE ALSO 🌈

the kernel file that started it all:

./drivers/net/ethernet/intel/i40e/i40e_dcb_nl.c

and the whole friend group (yes, all of them, no skipping, I said what I said 🔥):

that's the whole page, bestie 🧚💖 cute little sign-off: this one lives under ./drivers/net/ethernet/intel/i40e, and it's stamped October 2026. catch you in the next man 9 🎀✨

📦 where this page comes from