@deftypefun {int} {gnutls_idna_reverse_map} (const char * @var{input}, unsigned @var{ilen}, gnutls_datum_t * @var{out}, unsigned @var{flags}) @var{input}: contain the ACE (IDNA) formatted domain name @var{ilen}: the length of the provided string @var{out}: the result in an null-terminated allocated UTF-8 string @var{flags}: should be zero 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 @code{GNUTLS_E_UNIMPLEMENTED_FEATURE} . Note also, that this function will return an empty string if an empty string is provided as input. @strong{Returns:} A negative error code on error, or 0 on success. @strong{Since:} 3.5.8 @end deftypefun