MBSRTOWCS(3) Library Functions Manual MBSRTOWCS(3)

mbsnrtowcs, mbsnrtowcs_l, mbsrtowcs, mbsrtowcs_lconvert a character string to a wide-character string (restartable)

Standard C Library (libc, -lc)

#include <wchar.h>

size_t
mbsnrtowcs(wchar_t *restrict dst, const char **restrict src, size_t nms, size_t len, mbstate_t *restrict ps);

size_t
mbsrtowcs(wchar_t *restrict dst, const char **restrict src, size_t len, mbstate_t *restrict ps);

#include <wchar.h>
#include <xlocale.h>

size_t
mbsrtowcs_l(wchar_t *restrict dst, const char **restrict src, size_t len, mbstate_t *restrict ps, locale_t loc);

size_t
mbsnrtowcs_l(wchar_t *restrict dst, const char **restrict src, size_t nms, size_t len, mbstate_t *restrict ps, locale_t loc);

The () function converts a sequence of multibyte characters, pointed to indirectly by src, into a sequence of corresponding wide characters. It stores at most len of them in the wchar_t array pointed to by dst, until it encounters a terminating null character ('\0').

If dst is NULL, no characters are stored.

If dst is not NULL, the pointer pointed to by src is updated to point to the character after the one that conversion stopped at. If conversion stops because a null character is encountered, *src is set to NULL.

The mbstate_t argument, ps, is used to keep track of the shift state. If it is NULL, () uses an internal, static mbstate_t object, which is initialized to the initial conversion state at program startup.

The () function behaves identically to mbsrtowcs(), except that conversion stops after reading at most nms bytes from the buffer pointed to by src.

While the () and mbsnrtowcs() functions use the current locale, the () and () functions may be passed locales directly. See xlocale(3) for more information.

The mbsrtowcs() and mbsnrtowcs() functions return the number of wide characters stored in the array pointed to by dst if successful, otherwise it returns (size_t)-1.

The mbsrtowcs() and mbsnrtowcs() functions will fail if:

[]
An invalid multibyte character sequence was encountered.
[]
The conversion state is invalid.

mbrtowc(3), mbstowcs(3), multibyte(3), wcsrtombs(3), xlocale(3)

The mbsrtowcs() function conforms to ISO/IEC 9899:1999 (“ISO C99”).

The mbsnrtowcs() function is an extension to the standard.

July 21, 2004 macOS 15.2