int idn2_lookup_u8(const uint8_t * src, uint8_t ** lookupname, int flags);
- const uint8_t * src
input zero-terminated UTF-8 string in Unicode NFC normalized form.
- uint8_t ** lookupname
newly allocated output variable with name to lookup in DNS.
- int flags
optional idn2_flags to modify behaviour.
Perform IDNA2008 lookup string conversion on domain name src , as described in section 5 of RFC 5891. Note that the input string must be encoded in UTF-8 and be in Unicode NFC form.
Pass IDN2_NFC_INPUT in flags to convert input to NFC form before further processing. IDN2_TRANSITIONAL and IDN2_NONTRANSITIONAL do already imply IDN2_NFC_INPUT.
Pass IDN2_ALABEL_ROUNDTRIP in flags to convert any input A-labels to U-labels and perform additional testing. This is default since version 2.2. To switch this behavior off, pass IDN2_NO_ALABEL_ROUNDTRIP
Pass IDN2_TRANSITIONAL to enable Unicode TR46 transitional processing, and IDN2_NONTRANSITIONAL to enable Unicode TR46 non-transitional processing.
Multiple flags may be specified by binary or:ing them together.
After version 2.0.3: IDN2_USE_STD3_ASCII_RULES disabled by default. Previously we were eliminating non-STD3 characters from domain strings such as _443._tcp.example.com, or IPs 18.104.22.168/24 provided to libidn2 functions. That was an unexpected regression for applications switching from libidn and thus it is no longer applied by default. Use IDN2_USE_STD3_ASCII_RULES to enable that behavior again.
After version 0.11: lookupname may be NULL to test lookup of src without allocating memory.
On successful conversion IDN2_OK is returned, if the output domain or any label would have been too long IDN2_TOO_BIG_DOMAIN or IDN2_TOO_BIG_LABEL is returned, or another error code is returned.
The full documentation for libidn2 is maintained as a Texinfo manual. If the info and libidn2 programs are properly installed at your site, the command
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