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



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

SYNOPSIS
       #include <stdlib.h>

       size_t mbstowcs(wchar_t *dest, const char *src, size_t n);

DESCRIPTION
       If  dest  is  not  a  NULL  pointer, the mbstowcs() function converts the multibyte string src to a wide-character string
       starting at dest.  At most n wide characters are written to dest.  The conversion starts in the initial state.  The  con-
       version can stop for three reasons:

       1. An invalid multibyte sequence has been encountered.  In this case (size_t) -1 is returned.

       2. n  non-L'\0'  wide characters have been stored at dest.  In this case the number of wide characters written to dest is
          returned, but the shift state at this point is lost.

       3. The multibyte string has been completely converted, including the terminating '\0'.  In this case the number  of  wide
          characters written to dest, excluding the terminating L'\0' character, is returned.

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

       If  dest  is  NULL, n 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 order to avoid the case 2 above, the programmer should make sure n is greater or equal to mbstowcs(NULL,src,0)+1.

RETURN VALUE
       The mbstowcs() 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.

CONFORMING TO
       C99.

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

       The function mbsrtowcs(3) provides a better interface to the same functionality.

SEE ALSO
       mbsrtowcs(3)

COLOPHON
       This page is part of release 3.25 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                                                MBSTOWCS(3)