STRUCT ETHTOOL_USRIP6_SPEC(9)

🦋 struct ethtool_usrip6_spec — general flow specification for IPv6 ✨

okay bestie, so this is a page straight out of the Kernel API Manual (yes, the real one, struct ethtool_usrip6_spec(9)), and it's genuinely just a lil struct that describes an IPv6 flow 💖. That's it. That's the whole vibe. But like… it matters, so let's go 🫶

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✨ NAME ✨

struct ethtool_usrip6_spec — general flow specification for IPv6 🌈

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🎀 SYNOPSIS 🎀

struct ethtool_usrip6_spec {
    __be32 ip6src[4];
    __be32 ip6dst[4];
    __be32 l4_4_bytes;
    __u8 tclass;
    __u8 l4_proto;
 };

(watch the little stray space before the closing brace — that's literally how the original has it, so we keep it, no cap 💅)

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👑 Members 👑

here's the cast, the main characters of this struct, one by one 🎬

• ip6src — Source host 🌸 like, where the packet is coming from.
• ip6dst — Destination host 🎯 where it's going.
• l4_4_bytes — First 4 bytes of transport (layer 4) header 🔥 just the opening four bytes of the L4 header, nothing more.
• tclass — Traffic Class ⭐ the traffic class field, as advertised.
• l4_proto — Transport protocol number (nexthdr after any Extension Headers) 🦋 so if there's extension headers hanging around, this is the value after all of them — the real nexthdr.

ngl these field names are giving "I memorized the whole header layout" energy, and honestly? iconic 💀

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💜 SEE ALSO 💜

and now the friendship bracelet of cross-references, bestie — every single one, strapped together 💖 It all lives in the kernel file ./include/uapi/linux/ethtool.h:

struct ethtool_cmd(9), struct ethtool_drvinfo(9), struct ethtool_wolinfo(9), struct ethtool_regs(9), struct ethtool_eeprom(9), struct ethtool_eee(9), struct ethtool_modinfo(9), struct ethtool_coalesce(9), struct ethtool_ringparam(9), struct ethtool_channels(9), struct ethtool_pauseparam(9), enum ethtool_stringset(9), enum ethtool_mac_stats_src(9), enum ethtool_module_power_mode_policy(9), enum ethtool_module_power_mode(9), enum ethtool_c33_pse_ext_state(9), enum ethtool_c33_pse_ext_substate_mr_mps_valid(9), enum ethtool_c33_pse_ext_substate_error_condition(9), enum ethtool_c33_pse_ext_substate_mr_pse_enable(9), enum ethtool_c33_pse_ext_substate_option_detect_ted(9), enum ethtool_c33_pse_ext_substate_option_vport_lim(9), enum ethtool_c33_pse_ext_substate_ovld_detected(9), enum ethtool_c33_pse_ext_substate_power_not_available(9), enum ethtool_c33_pse_ext_substate_short_detected(9), enum ethtool_pse_types(9), enum ethtool_c33_pse_admin_state(9), enum ethtool_c33_pse_pw_d_status(9), enum ethtool_podl_pse_admin_state(9), enum ethtool_podl_pse_pw_d_status(9), enum ethtool_mm_verify_status(9), enum ethtool_module_fw_flash_status(9), struct ethtool_gstrings(9), struct ethtool_sset_info(9), enum ethtool_test_flags(9), struct ethtool_test(9), struct ethtool_stats(9), struct ethtool_perm_addr(9), struct ethtool_tcpip4_spec(9), struct ethtool_ah_espip4_spec(9), struct ethtool_usrip4_spec(9), struct ethtool_tcpip6_spec(9), struct ethtool_ah_espip6_spec(9), struct ethtool_flow_ext(9), struct ethtool_rx_flow_spec(9), struct ethtool_rxnfc(9), struct ethtool_rxfh_indir(9), struct ethtool_rxfh(9), struct ethtool_rx_ntuple_flow_spec(9), struct ethtool_rx_ntuple(9), struct ethtool_dump(9), struct ethtool_get_features_block(9), struct ethtool_gfeatures(9), struct ethtool_set_features_block(9), struct ethtool_sfeatures(9), struct ethtool_ts_info(9), struct ethtool_per_queue_op(9), struct ethtool_fecparam(9), enum ethtool_fec_config_bits(9), struct ethtool_link_settings(9), enum phy_upstream(9)

like, that's the whole extended friend group, go say hi 💅

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🧚 tiny sign-off before you go: this beauty is filed under ./include/uapi/linux, dated October 2026, and the manual page id is struct ethtool_usrip6_spec(9) — go read the neighbors, they're all in the SEE ALSO list anyway 😭💖

slay, you now understand IPv6 flow specs. periodt. 🔥👑