idn2_lookup_u8 − API function
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.
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 (not implemented yet). 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 220.127.116.11/24 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.
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