символьная строка в символьную строку (возможность перезапуска) (character string to a character string (restartable))
Пролог (Prolog)
This manual page is part of the POSIX Programmer's Manual. The
Linux implementation of this interface may differ (consult the
corresponding Linux manual page for details of Linux behavior),
or the interface may not be implemented on Linux.
Имя (Name)
wcsnrtombs, wcsrtombs — convert a wide-character string to a
character string (restartable)
Синопсис (Synopsis)
#include <wchar.h>
size_t wcsnrtombs(char *restrict dst, const wchar_t **restrict src,
size_t nwc, size_t len, mbstate_t *restrict ps);
size_t wcsrtombs(char *restrict dst, const wchar_t **restrict src,
size_t len, mbstate_t *restrict ps);
Описание (Description)
For wcsrtombs(): The functionality described on this reference
page is aligned with the ISO C standard. Any conflict between the
requirements described here and the ISO C standard is
unintentional. This volume of POSIX.1‐2017 defers to the ISO C
standard.
The wcsrtombs() function shall convert a sequence of wide
characters from the array indirectly pointed to by src into a
sequence of corresponding characters, beginning in the conversion
state described by the object pointed to by ps. If dst is not a
null pointer, the converted characters shall then be stored into
the array pointed to by dst. Conversion continues up to and
including a terminating null wide character, which shall also be
stored. Conversion shall stop earlier in the following cases:
* When a code is reached that does not correspond to a valid
character
* When the next character would exceed the limit of len total
bytes to be stored in the array pointed to by dst (and dst is
not a null pointer)
Each conversion shall take place as if by a call to the wcrtomb()
function.
If dst is not a null pointer, the pointer object pointed to by
src shall be assigned either a null pointer (if conversion
stopped due to reaching a terminating null wide character) or the
address just past the last wide character converted (if any). If
conversion stopped due to reaching a terminating null wide
character, the resulting state described shall be the initial
conversion state.
If ps is a null pointer, the wcsrtombs() function shall use its
own internal mbstate_t object, which is initialized at program
start-up to the initial conversion state. Otherwise, the
mbstate_t object pointed to by ps shall be used to completely
describe the current conversion state of the associated character
sequence.
The wcsnrtombs() and wcsrtombs() functions need not be thread-
safe if called with a NULL ps argument.
The wcsnrtombs() function shall be equivalent to the wcsrtombs()
function, except that the conversion is limited to the first nwc
wide characters.
The wcsrtombs() function shall not change the setting of errno if
successful.
The behavior of these functions shall be affected by the LC_CTYPE
category of the current locale.
The implementation shall behave as if no function defined in
System Interfaces volume of POSIX.1‐2017 calls these functions.
Возвращаемое значение (Return value)
If conversion stops because a code is reached that does not
correspond to a valid character, an encoding error occurs. In
this case, these functions shall store the value of the macro
[EILSEQ] in errno and return (size_t)-1; the conversion state is
undefined. Otherwise, these functions shall return the number of
bytes in the resulting character sequence, not including the
terminating null (if any).
Ошибки (Error)
These functions shall fail if:
EILSEQ A wide-character code does not correspond to a valid
character.
These functions may fail if:
EINVAL ps points to an object that contains an invalid conversion
state.
The following sections are informative.
Примеры (Examples)
None.
Использование в приложениях (Application usage)
None.
Обоснование (Rationale)
None.
Будущие направления (Future directions)
None.
Смотри также (See also)
mbsinit(3p), wcrtomb(3p)
The Base Definitions volume of POSIX.1‐2017, wchar.h(0p)
