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

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

       #include <wchar.h>

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

       If dest is not NULL, the wcsrtombs() function converts the wide-charac-
       ter string *src to a multibyte string starting at dest.	 At  most  len
       bytes  are  written to dest.  The shift state *ps is updated.  The con-
       version is effectively performed by  repeatedly	calling	 wcrtomb(dest,
       *src, ps), as long as this call succeeds, and then incrementing dest by
       the number of bytes written and *src by one.  The conversion  can  stop
       for three reasons:

       1. A wide character has been encountered that can not be represented as
	  a multibyte sequence (according to the  current  locale).   In  this
	  case,	  *src	is  left  pointing  to	the  invalid  wide  character,
	  (size_t) -1 is returned, and errno is set to EILSEQ.

       2. The length limit forces a stop.  In this case, *src is left pointing
	  to  the next wide character to be converted, and the number of bytes
	  written to dest is returned.

       3. The wide-character string has been completely	 converted,  including
	  the  terminating  null  wide	character  (L'\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 bytes written to dest,
	  excluding the terminating null byte ('\0'), is returned.

       If dest is NULL, len is ignored, and the conversion proceeds as	above,
       except that the converted bytes 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 wcsrtombs() function is used instead.

       The programmer must ensure that there is room for at least len bytes at

       The wcsrtombs() function returns the number of bytes that make  up  the
       converted  part	of  multibyte  sequence, not including the terminating
       null byte.  If a wide character was encountered which could not be con-
       verted, (size_t) -1 is returned, and errno set to EILSEQ.

       For   an	  explanation	of   the  terms	 used  in  this	 section,  see

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

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

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

       Passing NULL as ps is not multithread safe.

       iconv(3), mbsinit(3), wcrtomb(3), wcsnrtombs(3), wcstombs(3)

       This  page  is  part of release 4.10 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				  2015-08-08			  WCSRTOMBS(3)