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punycode_decode(3) libidn punycode_decode(3)


punycode_decode - API function


#include <punycode.h>

int punycode_decode(size_t input_length, const char [] input, size_t * output_length, punycode_uint [] output, unsigned char [] case_flags);


The number of ASCII code points in the input array.
An array of ASCII code points (0..7F).
The caller passes in the maximum number of code points that it can receive into the output array (which is also the maximum number of flags that it can receive into the
case_flags array, if case_flags is not a NULL pointer). On successful return it will contain the number of code points actually output (which is also the number of flags actually output, if case_flags is not a null pointer). The decoder will never need to output more code points than the number of ASCII code points in the input, because of the way the encoding is defined. The number of code points output cannot exceed the maximum possible value of a punycode_uint, even if the supplied
output_length is greater than that.
An array of code points like the input argument of punycode_encode() (see above).
A NULL pointer (if the flags are not needed by the caller) or an array of boolean values parallel to the output array. Nonzero (true, flagged) suggests that the corresponding Unicode character be forced to uppercase by the caller (if possible), and zero (false, unflagged) suggests that it be forced to lowercase (if possible). ASCII code points (0..7F) are output already in the proper case, but their flags will be set appropriately so that applying the flags would be harmless.


Converts Punycode to a sequence of code points (presumed to be Unicode code points).

Return value: The return value can be any of the Punycode_status values defined above. If not PUNYCODE_SUCCESS, then
output_length , output , and case_flags might contain garbage.


Report bugs to <>.
General guidelines for reporting bugs:
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Copyright © 2002-2021 Simon Josefsson.
Copying and distribution of this file, with or without modification, are permitted in any medium without royalty provided the copyright notice and this notice are preserved.


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