libwchar2 0.0.10
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wcsnrtombs - convert a wide-character string to a multibyte string
The wcsnrtombs() function is like the wcsrtombs(3) function, except that the number of wide characters to be converted, starting at *src, is limited to nwc.
If dest is not NULL
, the wcsnrtombs() function converts at most nwc wide characters from the wide-character string *src to a multibyte string starting at dest. At most len bytes are written to dest. The shift state *ps is updated. The conversion is effectively performed by repeatedly calling wcrtomb(dest, *src, ps), as long as this call suc- ceeds, and then incrementing dest by the number of bytes written and src by one. The conversion can stop for three reasons:
(size_t) -1
is returned, and errno is set to EILSEQ
.L
'\0', or the length limit forces a stop. In this case, *src is left pointing to the next wide character to be con- verted, and the number of bytes written to dest is returned.NULL
, and the number of bytes written to dest, excluding the ter- minating null byte '\0', is returned.If dest is NULL
, len is ignored, and the conversion proceeds as above, except that the converted bytes are not written out to memory, and that no destination length limit exists.
In both of the above cases, if ps is NULL
, a static anonymous state known only to the wcsnrtombs() function is used instead.
The programmer must ensure that there is room for at least len bytes at dest.
The wcsnrtombs() function returns the number of bytes that make up the converted part of multibyte sequence, not including the terminating null byte. If a wide character was encountered which could not be con- verted, (size_t) -1
is returned, and errno set to EILSEQ
.
The behavior of wcsnrtombs() depends on the LC_CTYPE
category of the current locale.
Passing NULL
as ps is not multithread safe.