idna_to_ascii_4i(3) API function


#include <idna.h>

int idna_to_ascii_4i(const uint32_t * in, size_t inlen, char * out, int flags);


const uint32_t * in
input array with unicode code points.
size_t inlen
length of input array with unicode code points.
char * out
output zero terminated string that must have room for at least 63 characters plus the terminating zero.
int flags


The ToASCII operation takes a sequence of Unicode code points that make up one domain label and transforms it into a sequence of code points in the ASCII range (0..7F). If ToASCII succeeds, the original sequence and the resulting sequence are equivalent labels.

It is important to note that the ToASCII operation can fail. ToASCII fails if any step of it fails. If any step of the ToASCII operation fails on any label in a domain name, that domain name MUST NOT be used as an internationalized domain name. The method for deadling with this failure is application-specific.

The inputs to ToASCII are a sequence of code points, the AllowUnassigned flag, and the UseSTD3ASCIIRules flag. The output of ToASCII is either a sequence of ASCII code points or a failure condition.

ToASCII never alters a sequence of code points that are all in the ASCII range to begin with (although it could fail). Applying the ToASCII operation multiple times has exactly the same effect as applying it just once.

Return value: Returns 0 on success, or an Idna_rc error code.


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Copyright © 2002-2015 Simon Josefsson.
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