plan9 man page for mbsrtowcs

MBSRTOWCS(3)						     Linux Programmer's Manual						      MBSRTOWCS(3)

NAME
       mbsrtowcs - convert a multibyte string to a wide-character string

SYNOPSIS
       #include <wchar.h>

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

DESCRIPTION
       If  dest is not NULL, the mbsrtowcs() function converts the multibyte string *src to a wide-character string starting 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  mbr-
       towc(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. len  non-L''  wide characters have been stored at dest.  In this case, *src is left pointing to the next multibyte sequence to be con-
	  verted, and the number of wide characters written to dest is returned.

       3. The multibyte string has been completely converted, including the terminating null wide character (''), which has the side	effect	of
	  bringing back *ps to the initial state.  In this case, *src is set to NULL, and the number of wide characters written to dest, excluding
	  the terminating null wide character, is returned.

       If dest is NULL, len is ignored, and the conversion proceeds as above, except that the converted wide characters are  not  written  out	to
       memory, and that no length limit exists.

       In both of the above cases, if ps is NULL, a static anonymous state known only to the mbsrtowcs() function is used instead.

       The programmer must ensure that there is room for at least len wide characters at dest.

RETURN VALUE
       The  mbsrtowcs() function returns the number of wide characters that make up the converted part of the wide-character string, not including
       the terminating null wide character.  If an invalid multibyte sequence was encountered, (size_t) -1 is returned, and errno set to EILSEQ.

ATTRIBUTES
       For an explanation of the terms used in this section, see attributes(7).

       +------------+---------------+------------------------------+
       |Interface   | Attribute     | Value			   |
       +------------+---------------+------------------------------+
       |mbsrtowcs() | Thread safety | MT-Unsafe race:mbsrtowcs/!ps |
       +------------+---------------+------------------------------+

CONFORMING TO
       POSIX.1-2001, POSIX.1-2008, C99.

NOTES
       The behavior of mbsrtowcs() depends on the LC_CTYPE category of the current locale.

       Passing NULL as ps is not multithread safe.

SEE ALSO
       iconv(3), mbrtowc(3), mbsinit(3), mbsnrtowcs(3), mbstowcs(3)

COLOPHON
       This page is part of release 4.15 of the Linux man-pages project.  A description of the project, information about reporting bugs, and  the
       latest version of this page, can be found at https://www.kernel.org/doc/man-pages/.

GNU
								    2017-09-15							      MBSRTOWCS(3)