home   contributing   bugs   download   online pages  

NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | CONFORMING TO | NOTES | SEE ALSO | COLOPHONThe Linux Programming Interface


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

NAME         top

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

SYNOPSIS         top

       #include <wchar.h>

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

DESCRIPTION         top

       If dest is not a NULL pointer, 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 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. len non-L'\0' wide characters have been stored at dest.  In this case *src
          is left pointing to the next multibyte sequence to be converted, and the
          number of wide characters written to dest is returned.

       3. The multibyte string has been completely converted, including the
          terminating '\0' (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 L'\0' 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 a NULL pointer, a static anonymous state
       only known 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         top

       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.

CONFORMING TO         top

       C99.

NOTES         top

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

       Passing NULL as ps is not multithread safe.

SEE ALSO         top

       iconv(3), mbsnrtowcs(3), mbstowcs(3)

COLOPHON         top

       This page is part of release 3.32 of the Linux man-pages project.  A
       description of the project, and information about reporting bugs, can be found
       at http://www.kernel.org/doc/man-pages/.

GNU                                   1999-07-25                         MBSRTOWCS(3)

HTML rendering created 2010-12-03 by Michael Kerrisk, author of The Linux Programming Interface

customisable
counter