std::c32rtomb

 

C++

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Null-terminated multibyte strings

Wide/multibyte conversions
mbsinit
mbtowc mbstowcs btowc mbrtowc mbsrtowcs mbrtoc16 (C++11) mbrtoc32 (C++11) mblen	wctomb wcstombs wctob wcrtomb wcsrtombs c16rtomb (C++11) c32rtomb (C++11) mbrlen
Types
mbstate_t

 

Defined in header <cuchar>
std::size_t c16rtomb( char* s, char32_t c32, std::mbstate_t* ps);		(since C++11)

Converts a 32-bit wide character to its narrow multibyte representation.

If s is not a null pointer, the function determines the number of bytes necessary to store the multibyte character representation of c32 (including any shift sequences), and stores the multibyte character representation in the character array whose first element is pointed to by s. At most MB_CUR_MAX bytes can be written by this function.

If s is a null pointer, the call is equivalent to std::c32rtomb(buf, U'\0', ps) for some internal buffer buf.

If c32 is the null wide character U'\0', a null byte is stored, preceded by any shift sequence necessary to restore the initial shift state and the conversion state parameter *ps is updated to represent 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. In any case, the multibyte encoding used by this function is specified by the currently active C locale.

Parameters

s	-	pointer to narrow character array where the multibyte character will be stored
c32	-	the 32-bit character to convert
ps	-	pointer to the conversion state object used when interpreting the multibyte string

Return value

On success, returns the number of bytes (including any shift sequences) written to the character array whose first element is pointed to by s. This value may be ​0​, e.g. when processing the first char32_t in multi-char32_t-character sequence (does not occur in UTF-32).

On failure (if c32 is not a valid 32-bit character), returns static_cast<std::size_t>(-1), stores EILSEQ in errno, and leaves *ps in unspecified state.

See also

mbrtoc32 (C++11)	generate the next 32-bit wide character from a narrow multibyte string (function)
do_out [virtual]	converts a string from internT to externT, such as when writing to file (virtual protected member function of std::codecvt)