calipso_tlv_len(9)

📦 version 7.3.1, in nixpkgs unstable

🎀 calipso_tlv_len(9) 🎀

okay bestie, welcome to calipso_tlv_len(9) — straight outta the Kernel API Manual and ready to explain this tiny TLV-length moment. 💖 This page is short, but it’s lowkey iconic.

✨ NAME ✨

calipso_tlv_len — returns the length of the TLV. That’s the whole assignment, and she ate. 💅

💻 SYNOPSIS 💻

int calipso_tlv_len (struct ipv6_opt_hdr *opt , unsigned int offset );

🫶 ARGUMENTS 🫶

  • opt — the option header, bestie. Type check: struct ipv6_opt_hdr *. This is the header we’re looking inside. 🌸
  • offset — the offset of the TLV within the header. Type check: unsigned int. It’s giving “start looking here” energy. ✨

🧚 DESCRIPTION 🧚

okay so here’s the tea: this function returns the length of the TLV option at offset offset within the option header opt. Before it hands you that length, it checks that the entire TLV actually fits inside the option header. If the whole TLV does not fit, it returns a negative value. 😭

if you get a negative value back, that’s the “nope, it doesn’t fit” signal. no cap. 🚩

🌟 SEE ALSO 🌟

the kernel file is ./net/ipv6/calipso.c, and the whole CALIPSO squad pulls up like:

xoxo, from ./net/ipv6 🌸, dated October 2026 🎀, on page calipso_tlv_len(9) 💅

📦 where this page comes from