IDN2(1)

📦
version 2.3.8 · 11 versions
, in alpine 3.23, alpine 3.24, arch rolling, fedora 43, fedora 44, nixos 26.05, nixpkgs unstable, opensuse-leap 16.0

💖 idn2 — the Libidn2 Internationalized Domain Names conversion tool 💖

okay bestie, pull up a chair, because we're about to talk about the idn2 manual page from User Commands and it's actually so much cooler than it sounds. no cap. 🦋

✨ NAME ✨

idn2 — the Libidn2 Internationalized Domain Names conversion tool 🎀

🌈 SYNOPSIS 🌈

idn2 [OPTION]... [STRINGS]...

👑 DESCRIPTION 👑

so like. the idn2 tool takes DNS domains and converts them from UTF-8 into ASCII compatible encoding (ACE) form — which is the form the DNS protocol actually uses. the encoding format in question? that's the Internationalized Domain Name (IDNA2008/TR46) format. periodt. 💅

Internationalized Domain Name (IDNA2008) convert STRINGS, or standard input. yes, she reads from stdin too, she's versatile like that. 🫶

this is the command line interface to the Libidn2 implementation of IDNA2008.

⚠️ important vibe check: all strings are expected to be encoded in the locale charset.

and here's a little gotcha that WILL trip you up if nobody tells you: if you wanna process a string that starts with -, like for example -foo, you gotta use -- to signal the end of parameters, like this:

idn2 --quiet -- -foo

Mandatory arguments to long options are mandatory for short options too. (yes bestie that sentence is real and yes it applies to every single one of these, slay.) ✨

🌸 OPTIONS 🌸

  • -h, --help — print help and exit, the classic "wait what do I do" move 💀
  • -V, --version — print version and exit 📌
  • -d, --decode — decode (punycode) domain name 🔄
  • -l, --lookup — lookup domain name — and yes, this is the default 👀
  • -r, --register — register label 📝
  • -T, --tr46t — enable TR46 transitional processing 🧚
  • -N, --tr46nt — enable TR46 non-transitional processing 🌈
  • --no-tr46 — disable TR46 processing 🚫
  • --usestd3asciirules — enable STD3 ASCII rules 📏
  • --no-alabelroundtrip — disable A-label roundtrip for lookups 🔁
  • --debug — print debugging information 🐛
  • --quiet — silent operation 🤫

🫶 AUTHOR 🫶

Written by Simon Josefsson, Tim Ruehsen. legends, honestly. 👑

😭 REPORTING BUGS 😭

found a bug? first of all, relatable. second of all:

Copyright © 2011-2025 Simon Josefsson, Tim Ruehsen. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>.

This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. (read that again bestie, NO WARRANTY, I'm not playing 😭)

🦋 SEE ALSO 🦋

The full documentation for idn2 is maintained as a Texinfo manual. If the info and idn2 programs are properly installed at your site, the command

info idn2

should give you access to the complete manual. go read it, it's giving ✨main character reference material✨.

okay that's the whole page!! you understood it, I'm so proud of you, bestie. 🥹💖

this was Libidn2 2.3.8, dated March 2025, and you can find it filed under IDN2(1) if you ever need to find her again. mwah. 💅🎀

📦 where this page comes from