nlmsg_put_answer(9)

💅 nlmsg_put_answer(9) — like, the Kernel API Manual page you actually want to read ✨

okay so bestie, this is nlmsg_put_answer from the Kernel API Manual, and it's genuinely one of the more lowkey-important little helpers in the netlink world, so let's get into it 🫶

🎀 NAME 🎀

nlmsg_put_answer — add a new callback based netlink message to an skb

✨ SYNOPSIS ✨

struct nlmsghdr * nlmsg_put_answer (struct sk_buff *skb , struct netlink_callback *cb , int type , int payload , int flags );

🌸 ARGUMENTS 🌸

she takes five things, and every single one matters, no skips:

• skb — the socket buffer where the message is gonna get stored 🧺 (this is the home, the whole vibe lives here)
• cb — the netlink callback 💫
• type — the message type 🏷️
• payload — how long the message payload is 📏
• flags — the message flags 🚩

👑 RETURN 👑

she returns NULL if the tailroom of the skb is insufficient to store the message header and the payload 😭 — like, no room, no message, that's just the rules.

ngl bestie, check your tailroom. NULL back means the skb literally could not fit it. 💀

🌈 SEE ALSO 🌈

the kernel file lives at ./include/net/netlink.h and honestly the whole netlink friend group shows up here — struct nla_policy(9), struct nl_info(9), enum netlink_validation(9), nlmsg_msg_size(9), nlmsg_total_size(9), nlmsg_padlen(9), nlmsg_data(9), nlmsg_len(9), nlmsg_payload(9), nlmsg_attrdata(9), nlmsg_attrlen(9), nlmsg_ok(9), nlmsg_next(9), nla_parse(9), nla_parse_deprecated(9), nla_parse_deprecated_strict(9), __nlmsg_parse(9), nlmsg_parse(9), nlmsg_parse_deprecated(9), nlmsg_parse_deprecated_strict(9), nlmsg_find_attr(9), nla_validate_deprecated(9), nla_validate(9), nlmsg_validate_deprecated(9), nlmsg_report(9), nlmsg_seq(9), nlmsg_for_each_attr(9), nlmsg_for_each_attr_type(9), nlmsg_put(9), nlmsg_append(9), nlmsg_new(9), nlmsg_new_large(9), nlmsg_end(9), nlmsg_get_pos(9), nlmsg_trim(9), nlmsg_cancel(9), nlmsg_free(9), nlmsg_consume(9), nlmsg_multicast_filtered(9), nlmsg_multicast(9), nlmsg_unicast(9), nlmsg_for_each_msg(9), nl_dump_check_consistent(9), nla_attr_size(9), nla_total_size(9), nla_padlen(9), nla_type(9), nla_data(9), nla_len(9), nla_ok(9), nla_next(9), nla_find_nested(9), nla_parse_nested(9), nla_parse_nested_deprecated(9), nla_put_u8(9), nla_put_u16(9), nla_put_be16(9), nla_put_net16(9), nla_put_le16(9), nla_put_u32(9), nla_put_uint(9), nla_put_be32(9), nla_put_net32(9), nla_put_le32(9), nla_put_u64_64bit(9), nla_put_be64(9), nla_put_net64(9), nla_put_le64(9), nla_put_s8(9), nla_put_s16(9), nla_put_s32(9), nla_put_s64(9), nla_put_sint(9), nla_put_string(9), nla_put_flag(9), nla_put_msecs(9), nla_put_in_addr(9), nla_put_in6_addr(9), nla_put_bitfield32(9), nla_get_u32(9), nla_get_u32_default(9), nla_get_be32(9), nla_get_be32_default(9), nla_get_le32(9), nla_get_le32_default(9), nla_get_u16(9), nla_get_u16_default(9), nla_get_be16(9), nla_get_be16_default(9), nla_get_le16(9), nla_get_le16_default(9), nla_get_u8(9), nla_get_u8_default(9), nla_get_u64(9), nla_get_u64_default(9), nla_get_uint(9), nla_get_uint_default(9), nla_get_be64(9), nla_get_be64_default(9), nla_get_le64(9), nla_get_le64_default(9), nla_get_s32(9), nla_get_s32_default(9), nla_get_s16(9), nla_get_s16_default(9), nla_get_s8(9), nla_get_s8_default(9), nla_get_s64(9), nla_get_s64_default(9), nla_get_sint(9), nla_get_sint_default(9), nla_get_flag(9), nla_get_msecs(9), nla_get_msecs_default(9), nla_get_in_addr(9), nla_get_in_addr_default(9), nla_get_in6_addr(9), nla_get_bitfield32(9), nla_memdup(9), nla_nest_start_noflag(9), nla_nest_start(9), nla_nest_end(9), nla_nest_end_safe(9), nla_nest_cancel(9), nla_put_empty_nest(9), __nla_validate_nested(9), nla_need_padding_for_64bit(9), nla_align_64bit(9), nla_total_size_64bit(9), nla_for_each_attr(9), nla_for_each_attr_type(9), nla_for_each_nested(9), nla_for_each_nested_type(9), nla_is_last(9) 💖

k that's the whole page bestie, go write some netlink code, you're literally gonna slay 💅✨

mwah 💋 — this one's from ./include/net, dated October 2026, and yeah she's iconic, periodt 🎀