COAP(7)

📦
version 4.3.5b · 12 versions
, in fedora 43, fedora 44

🌸 COAP(7) — the libcoap tea, served piping hot 💅

okay bestie, gather round, because this is the page — it's the overview of the whole libcoap library, from the libcoap Manual. Think of it as the group chat pinned message that tells you where everything else lives. 🫶

✨ SYNOPSIS ✨

Literally just a summary of the different libcoap API manual pages. That's it. That's the synopsis. She's short, she's sweet, she's a table of contents with main character energy. 👑

💖 DESCRIPTION 💖

so. libcoap is a C implementation of a lightweight application-protocol for devices that are constrained by their resources — and when I say constrained I mean computing power, RF range, memory, bandwidth, or network packet sizes. Tiny little devices, huge little vibes. 🦋

This protocol, CoAP, is standardized by the IETF as RFC7252. For further information related to CoAP, see http://coap.technology. no cap, that's the link, go look. ✨

Documentation for the specific library calls — with examples, because we're not monsters — can be found in the man pages referred to in SEE ALSO. it's giving "we made you a whole reading list". 📚

Further information can be found in the include header files, with example code provided in the examples directory. iconic behavior honestly. 🎀

NOTE: This documentation is a work in progress. Any missing information can be found in the include header files along with example code provided in the examples directory. not me admitting the docs are still cooking 😭 but fr fr, the headers got you.

🌈 SEE ALSO 🌈

the whole friend group, one by one, no one left out:

(yes, coap_init() really is written without the (3). we keep it exactly as she is. 💅)

For example executables, see coap-client(5), coap-rd(5) and coap-server(5) 🧚

For OSCORE configuration, see coap-oscore-conf(5) 🔐

📖 FURTHER INFORMATION 📖

See:

  • "RFC7252: The Constrained Application Protocol (CoAP)"
  • "RFC7390: Group Communication for the Constrained Application Protocol (CoAP)"
  • "RFC7641: Observing Resources in the Constrained Application Protocol (CoAP)"
  • "RFC7959: Block-Wise Transfers in the Constrained Application Protocol (CoAP)"
  • "RFC7967: Constrained Application Protocol (CoAP) Option for No Server Response"
  • "RFC8132: PATCH and FETCH Methods for the Constrained Application Protocol (CoAP)"
  • "RFC8323: CoAP (Constrained Application Protocol) over TCP, TLS, and WebSockets"
  • "RFC8516: "Too Many Requests" Response Code for the Constrained Application Protocol"
  • "RFC8613: Object Security for Constrained RESTful Environments (OSCORE)"
  • "RFC8768: Constrained Application Protocol (CoAP) Hop-Limit Option"
  • "RFC8974: Extended Tokens and Stateless Clients in the Constrained Application Protocol (CoAP)"
  • "RFC9175: CoAP: Echo, Request-Tag, and Token Processing"
  • "RFC9177: Constrained Application Protocol (CoAP) Block-Wise Transfer Options Supporting Robust Transmission"

for further information. yes bestie, that's thirteen RFCs. read them all, hydrate, take breaks. 🌸

🐛 BUGS 🐛

found a bug? Please raise an issue on GitHub at https://github.com/obgm/libcoap/issues to report any bugs. we wanna know, fr fr. 👀

got a fix instead? Please raise a Pull Request at https://github.com/obgm/libcoap/pulls for any fixes. slay, we love a contributor. 🔥

👑 AUTHORS 👑

The libcoap project <libcoap-developers@lists.sourceforge.net> — the whole squad. 🫶

and that's the page, bestie. this is coap version 4.3.5b, dated 04/17/2026, straight from the COAP(7) man page. periodt. 💜 ✨ 🎀

📦 where this page comes from