1idn2_to_ascii_4i(3) libidn2 idn2_to_ascii_4i(3)
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6 idn2_to_ascii_4i - API function
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9 #include <idn2.h>
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11 int idn2_to_ascii_4i(const uint32_t * input, size_t inlen, char * out‐
12 put, int flags);
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15 const uint32_t * input
16 zero terminated input Unicode (UCS-4) string.
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18 size_t inlen
19 number of elements in input .
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21 char * output
22 output zero terminated string that must have room for at
23 least 63 characters plus the terminating zero.
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25 int flags optional idn2_flags to modify behaviour.
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28 THIS FUNCTION HAS BEEN DEPRECATED DUE TO A DESIGN FLAW. USE
29 idn2_to_ascii_4i2() INSTEAD !
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31 The ToASCII operation takes a sequence of Unicode code points that make
32 up one domain label and transforms it into a sequence of code points in
33 the ASCII range (0..7F). If ToASCII succeeds, the original sequence and
34 the resulting sequence are equivalent labels.
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36 It is important to note that the ToASCII operation can fail. ToASCII
37 fails if any step of it fails. If any step of the ToASCII operation
38 fails on any label in a domain name, that domain name MUST NOT be used
39 as an internationalized domain name. The method for dealing with this
40 failure is application-specific.
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42 The inputs to ToASCII are a sequence of code points.
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44 ToASCII never alters a sequence of code points that are all in the
45 ASCII range to begin with (although it could fail). Applying the
46 ToASCII operation multiple effect as applying it just once.
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48 The default behavior of this function (when flags are zero) is to apply
49 the IDNA2008 rules without the TR46 amendments. As the TR46 non-transi‐
50 tional processing is nowadays ubiquitous, when unsure, it is recom‐
51 mended to call this function with the IDN2_NONTRANSITIONAL and the
52 IDN2_NFC_INPUT flags for compatibility with other software.
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54 Return value: Returns IDN2_OK on success, or error code.
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57 2.0.0
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60 2.1.1: Use idn2_to_ascii_4i2().
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63 The full documentation for libidn2 is maintained as a Texinfo manual.
64 If the info and libidn2 programs are properly installed at your site,
65 the command
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67 info libidn2
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69 should give you access to the complete manual. As an alternative you
70 may obtain the manual from:
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72 https://www.gnu.org/software/libidn/libidn2/manual/
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74libidn2 2.3.1.48-1925 idn2_to_ascii_4i(3)