Namespaces
Variants
Views
Actions

mbrtoc32

From cppreference.com
< c‎ | string‎ | multibyte
Revision as of 17:11, 2 November 2012 by P12bot (Talk | contribs)

Defined in header <cuchar>
size_t mbrtoc32( char32_t* pc32, const char* s, size_t n, mbstate_t* ps );
(since C11)

Converts a narrow multibyte character to its 32-bit character representation (typically, UTF-32).

If s is not a null pointer, inspects at most n bytes of the multibyte character string, beginning with the byte pointed to by s to determine the number of bytes necessary to complete the next multibyte character (including any shift sequences). If the function determines that the next multibyte character in s is complete and valid, converts it to the corresponding 32-bit character and stores it in *pc32 (if pc32 is not null).

If the multibyte character in *s corresponds to a multi-char32_t sequence (not possible with UTF-32), then after the first call to this function, *ps is updated in such a way that the next calls to mbrtoc32 will write out the additional char32_t, without considering *s.

If s is a null pointer, the values of n and pc32 are ignored and the call is equivalent to mbrtoc32(NULL, "", 1, ps).

If the wide character produced is the null character, the conversion state *ps represents the initial shift state.

If the macro __STDC_UTF_32__ is defined, the 32-bit encoding used by this function is UTF-32, otherwise it is implementation-defined.

Parameters

pc32 - pointer to the location where the resulting 32-bit character will be written
s - pointer to the multibyte character string used as input
n - limit on the number of bytes in s that can be examined
ps - pointer to the conversion state object used when interpreting the multibyte string

Return value

The first of the following that applies:

  • 0 if the character converted from s (and stored in *pc32 if non-null) was the null character
  • the number of bytes [1...n] of the multibyte character successfully converted from s
  • -3 if the next char32_t from a multi-char32_t character has now been written to *pc32. No bytes are processed from the input in this case.
  • -2 if the next n bytes constitute an incomplete, but so far valid, multibyte character. Nothing is written to *pc32.
  • -1 if encoding error occurs. Nothing is written to *pc32, the value EILSEQ is stored in errno and the value if *ps is unspecified.

See also

Template:c/string/multibyte/dcl list c32rtomb
C++ documentation for mbrtoc32