ethnl_update_bitfield32(9)

💅 ethnl_update_bitfield32 — a lil' kernel API manual moment ✨

okay so bestie, welcome to the Kernel API Manual entry for ethnl_update_bitfield32(9) — yes that's the whole name, she's long but she's iconic 🎀

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✨ NAME ✨

ethnl_update_bitfield32 — update a u32 value from an NLA_BITFIELD32 attribute 🦋

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🌸 SYNOPSIS 🌸

void ethnl_update_bitfield32 (u32 *dst , const struct nlattr *attr ,
bool *mod );

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💖 ARGUMENTS 💖

• dst — the value you're updating, bestie. that's the one getting a glow-up 💅
• attr — the netlink attribute holding the new value, or null if there's nothing to see here 🙈
• mod — a pointer to a bool that keeps track of whether anything actually got modified 👑

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🔥 DESCRIPTION 🔥

So here's the vibe: she updates the bits in the u32 value that are set in the attribute's mask — swapping them over to the values from the attribute's value ✨

But fr fr, if attr is null, or the value wouldn't change at all? She does nothing. literally nothing. not a single thing. 💀

Otherwise — and only otherwise — she sets the bool pointed to by mod to true, so everyone knows a modification happened 🫶

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🦋 SEE ALSO 🦋

Kernel file ./net/ethtool/netlink.h, plus the whole friend group:

• ethnl_strz_size(9)
• ethnl_put_strz(9)
• ethnl_update_u32(9)
• ethnl_update_u8(9)
• ethnl_update_u8_u32(9)
• ethnl_update_bool32(9)
• ethnl_update_bool(9)
• ethnl_update_binary(9)
• ethnl_reply_header_size(9)
• struct ethnl_req_info(9)
• ethnl_req_get_phydev(9)
• struct ethnl_reply_data(9)
• struct ethnl_request_ops(9)

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ngl this one's short but she ate. no cap. 🌈

okay that's the whole page bestie, ily, go update some bitfields 💜

— source version <pink>./net/ethtool</pink>, dated October 2026, signed off with a kiss 🎀⭐🍓