Mac Forum / Programming / CodeWarrior / January 2006

Hi!

It seems to be that the MSL lib implements the mbstowcs function
differently from Apple's implementation in case the first pointer is NULL.
Apple's implementation seems to return the length of the "in"-string
while MSL always returns 0. When looking at Apple's man pages even
(size_t) -1 should be returned.

Now, what is the right functionality?

Hartwig

PS: man pages from Apple to mbstowc

     #include <stdlib.h>

     size_t
     mbstowcs(wchar_t * restrict wcstring, const char * restrict mbstring,
         size_t nwchars);

     #include <xlocale.h>

     size_t
     mbstowcs_l(wchar_t * restrict wcstring, const char * restrict
mbstring,
         size_t nwchars, locale_t loc);

DESCRIPTION
     The mbstowcs() function converts a multibyte character string mbstring
     beginning in the initial conversion state into a wide character string
     wcstring.  No more than nwchars wide characters are stored.  A
terminat-terminating
     ing null wide character is appended if there is room.

     While the mbstowcs() function uses the current locale, the
mbstowcs_l()
     function may be passed a locale directly. See xlocale(3) for more
infor-information.
     mation.

RETURN VALUES
     The mbstowcs() function returns the number of wide characters
converted,
     not counting any terminating null wide character, or -1 if an invalid
     multibyte character was encountered.

ERRORS
     The mbstowcs() function will fail if:

     [EILSEQ]           An invalid multibyte sequence was detected.

     [EINVAL]           The conversion state is invalid.