#include <wchar.h>

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

   Feature Test Macro Requirements for glibc (see feature_test_macros(7)):

           Since glibc 2.10:
               _XOPEN_SOURCE >= 700 || _POSIX_C_SOURCE >= 200809L
           Before glibc 2.10:

       The  mbsnrtowcs()  function  is  like the mbsrtowcs(3) function, except
       that the number of bytes to be converted, starting at *src, is  limited
       to nms.

       If  dest  is  not  NULL, the mbsnrtowcs() function converts at most nms
       bytes from the multibyte string *src to a wide-character string  start-
       ing  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. The nms limit forces a stop, or 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 null wide character ('\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,  exclud-
          ing 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  mem-
       ory, 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 mbsnrtowcs() function is used instead.

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

       The  mbsnrtowcs()  function  returns the number of wide characters that


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

       Passing NULL as ps is not multithread safe.

       iconv(3), mbrtowc(3) mbsinit(3), mbsrtowcs(3)

       This page is part of release 4.04 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

GNU                               2015-04-19                     MBSNRTOWCS(3)
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