Linux command
idn 命令
文本
涉及管道、覆盖或删除，执行前请先确认路径和参数。
常用示例
Encode a Unicode domain to ACE/Punycode (default mode)
echo "münchen.de" | idn
Decode a Punycode domain back to Unicode
echo "xn--mnchen-3ya.de" | idn --idna-to-unicode
Apply Nameprep stringprep to input
echo "[string]" | idn --stringprep
Explicitly run IDNA ToASCII on an argument
idn --idna-to-ascii [münchen.de]
Encode or decode raw Punycode (no IDNA wrapping)
echo "[label]" | idn --punycode-encode
Quiet mode (suppress informational messages)
idn --quiet [domain]
说明
idn converts internationalized domain names between Unicode and ASCII-Compatible Encoding (ACE / Punycode). It implements the IDNA (Internationalized Domain Names in Applications) standard, allowing domain names with non-ASCII characters to be represented in the DNS. The encoding pipeline applies Nameprep stringprep (case folding, NFKC normalization, prohibited-character checks) before Punycode encoding. ACE-encoded labels use the xn-- prefix. The tool reads strings from command-line arguments, or from standard input if none are supplied. Input is expected in the locale's preferred charset; override this by setting the CHARSET environment variable. To process a string starting with `-`, use `--` to mark the end of options (e.g. `idn --quiet -a -- -foo`).
参数
- -a, --idna-to-ascii
- Convert input to ACE according to IDNA. This is the default mode.
- -u, --idna-to-unicode
- Convert input from ACE (Punycode) back to Unicode using IDNA.
- -s, --stringprep
- Prepare the string according to the Nameprep profile.
- -e, --punycode-encode
- Encode raw input with the Punycode algorithm, without IDNA pre/post processing.
- -d, --punycode-decode
- Decode raw Punycode input, without IDNA pre/post processing.
- -n, --nfkc
- Normalize input according to Unicode v3.2 NFKC.
- -p _profile_, --profile=_profile_
- Use the named stringprep profile. Valid values: `Nameprep`, `iSCSI`, `Nodeprep`, `Resourceprep`, `trace`, `SASLprep`.
- --allow-unassigned
- Toggle the IDNA `AllowUnassigned` flag (default off).
- --usestd3asciirules
- Toggle the IDNA `UseSTD3ASCIIRules` flag (default off); forbids non-LDH characters.
- --no-tld
- Skip TLD-specific validity checks (only affects `--idna-to-ascii` / `--idna-to-unicode`).
- --quiet
- Silent operation.
- --debug
- Print debugging information, including the detected character set.
- -h, --help
- Print help and exit.
- -V, --version
- Print version and exit.
FAQ
What is the idn command used for?
idn converts internationalized domain names between Unicode and ASCII-Compatible Encoding (ACE / Punycode). It implements the IDNA (Internationalized Domain Names in Applications) standard, allowing domain names with non-ASCII characters to be represented in the DNS. The encoding pipeline applies Nameprep stringprep (case folding, NFKC normalization, prohibited-character checks) before Punycode encoding. ACE-encoded labels use the xn-- prefix. The tool reads strings from command-line arguments, or from standard input if none are supplied. Input is expected in the locale's preferred charset; override this by setting the CHARSET environment variable. To process a string starting with `-`, use `--` to mark the end of options (e.g. `idn --quiet -a -- -foo`).
How do I run a basic idn example?
Run `echo "münchen.de" | idn` in a terminal, then adjust file names, paths, flags, or remote targets for your system.
What does -a, --idna-to-ascii do in idn?
Convert input to ACE according to IDNA. This is the default mode.