MBSNRTOWCS(3) Linux Programmer's Manual MBSNRTOWCS(3)
mbsnrtowcs - convert a multibyte string to a wide-character string
size_t mbsnrtowcs(wchar_t *dest, const char **src,
size_t nms, size_t len, mbstate_t *ps);
Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
Since glibc 2.10:
_POSIX_C_SOURCE >= 200809L
Before glibc 2.10:
The mbsnrtowcs() function is like the mbsrtowcs(3) function, except that the number of bytes to be converted, starting at *src, is limited
to at most nms bytes.
If dest is not NULL, the mbsnrtowcs() function converts at most nms bytes from the multibyte string *src to a wide-character string start-
ing at dest. At most len wide characters are written to dest. The shift state *ps is updated. The conversion is effectively performed by
repeatedly calling mbrtowc(dest, *src, n, ps) where n is some positive number, as long as this call succeeds, and then incrementing dest by
one and *src by the number of bytes consumed. The conversion can stop for three reasons:
1. An invalid multibyte sequence has been encountered. In this case, *src is left pointing to the invalid multibyte sequence, (size_t) -1
is returned, and errno is set to EILSEQ.
2. The nms limit forces a stop, or len non-L'