преобразовать широкий символ в многобайтовую последовательность (convert a wide character to a multibyte sequence)
Имя (Name)
wcrtomb - convert a wide character to a multibyte sequence
Синопсис (Synopsis)
#include <wchar.h>
size_t wcrtomb(char *restrict s, wchar_t wc, mbstate_t *restrict ps);
Описание (Description)
The main case for this function is when s is not NULL and wc is
not a null wide character (L'\0'). In this case, the wcrtomb()
function converts the wide character wc to its multibyte
representation and stores it at the beginning of the character
array pointed to by s. It updates the shift state *ps, and
returns the length of said multibyte representation, that is, the
number of bytes written at s.
A different case is when s is not NULL, but wc is a null wide
character (L'\0'). In this case, the wcrtomb() function stores
at the character array pointed to by s the shift sequence needed
to bring *ps back to the initial state, followed by a '\0' byte.
It updates the shift state *ps (i.e., brings it into the initial
state), and returns the length of the shift sequence plus one,
that is, the number of bytes written at s.
A third case is when s is NULL. In this case, wc is ignored, and
the function effectively returns
wcrtomb(buf, L'\0', ps)
where buf is an internal anonymous buffer.
In all of the above cases, if ps is NULL, a static anonymous
state known only to the wcrtomb() function is used instead.
Возвращаемое значение (Return value)
The wcrtomb() function returns the number of bytes that have been
or would have been written to the byte array at s. If wc can not
be represented as a multibyte sequence (according to the current
locale), (size_t) -1 is returned, and errno set to EILSEQ.
Атрибуты (Attributes)
For an explanation of the terms used in this section, see
attributes(7).
┌───────────────────┬───────────────┬────────────────────────────┐
│Interface │ Attribute │ Value │
├───────────────────┼───────────────┼────────────────────────────┤
│wcrtomb() │ Thread safety │ MT-Unsafe race:wcrtomb/!ps │
└───────────────────┴───────────────┴────────────────────────────┘
Стандарты (Conforming to)
POSIX.1-2001, POSIX.1-2008, C99.
Примечание (Note)
The behavior of wcrtomb() depends on the LC_CTYPE category of the
current locale.
Passing NULL as ps is not multithread safe.
Смотри также (See also)
mbsinit(3), wcsrtombs(3)
