---
name: "gnutls_idna_reverse_map"
section: "3"
platform: "linux"
package: "gnutls"
version: "3.8.13-3"
release: "Arch Linux 2026-11-01"
platforms: ["linux"]
url: "https://new.carta.tech/gnutls_idna_reverse_map"
---

# gnutls\_idna\_reverse\_map(3)

API function

## NAME

gnutls\_idna\_reverse\_map - API function

## SYNOPSIS

**#include \<gnutls/gnutls.h\>**

**int gnutls\_idna\_reverse\_map(const char \*** *input***, unsigned** *ilen***, gnutls\_datum\_t \*** *out***, unsigned** *flags***);**

## ARGUMENTS

- const char \* input

  contain the ACE (IDNA) formatted domain name

- unsigned ilen

  the length of the provided string

- gnutls\_datum\_t \* out

  the result in an null-terminated allocated UTF-8 string

- unsigned flags

  should be zero

## DESCRIPTION

This function will convert an ACE (ASCII-encoded) domain name to a UTF-8 domain name.

If GnuTLS is compiled without IDNA support, then this function will return **GNUTLS\_E\_UNIMPLEMENTED\_FEATURE**.

Note also, that this function will return an empty string if an empty string is provided as input.

## RETURNS

A negative error code on error, or 0 on success.

## SINCE

3\.5.8

## REPORTING BUGS

Report bugs to \<bugs@gnutls.org\>.\
 Home page: https://www.gnutls.org

## COPYRIGHT

Copyright © 2001-2023 Free Software Foundation, Inc., and others.\
 Copying and distribution of this file, with or without modification, are permitted in any medium without royalty provided the copyright notice and this notice are preserved.

## SEE ALSO

The full documentation for **gnutls** is maintained as a Texinfo manual. If the /usr/share/doc/gnutls/ directory does not contain the HTML form visit

- https://www.gnutls.org/manual/