PROLOG

       This  manual  page  is part of the POSIX Programmer's Manual.  The Linux implementation of this interface
       may differ (consult the corresponding Linux manual page for details of Linux behavior), or the  interface
       may not be implemented on Linux.

NAME

       wcstombs — convert a wide-character string to a character string

SYNOPSIS

       #include <stdlib.h>

       size_t wcstombs(char *restrict s, const wchar_t *restrict pwcs,
           size_t n);

DESCRIPTION

       The  functionality  described  on  this  reference  page is aligned with the ISO C standard. Any conflict
       between the requirements described  here  and  the  ISO C  standard  is  unintentional.  This  volume  of
       POSIX.1‐2008 defers to the ISO C standard.

       The  wcstombs() function shall convert the sequence of wide-character codes that are in the array pointed
       to by pwcs into a sequence of characters  that  begins  in  the  initial  shift  state  and  store  these
       characters  into  the  array  pointed  to by s, stopping if a character would exceed the limit of n total
       bytes or if a null byte is stored. Each wide-character code shall  be  converted  as  if  by  a  call  to
       wctomb(), except that the shift state of wctomb() shall not be affected.

       The behavior of this function shall be affected by the LC_CTYPE category of the current locale.

       No  more  than  n  bytes  shall be modified in the array pointed to by s.  If copying takes place between
       objects that overlap, the behavior is undefined.  If s is a null pointer,  wcstombs()  shall  return  the
       length required to convert the entire array regardless of the value of n, but no values are stored.

RETURN VALUE

       If  a  wide-character  code  is encountered that does not correspond to a valid character (of one or more
       bytes each), wcstombs() shall return (size_t)−1. Otherwise, wcstombs() shall return the number  of  bytes
       stored  in  the  character  array,  not including any terminating null byte. The array shall not be null-
       terminated if the value returned is n.

ERRORS

       The wcstombs() function shall fail if:

       EILSEQ A wide-character code does not correspond to a valid character.

       The following sections are informative.

EXAMPLES

       None.

APPLICATION USAGE

       None.

RATIONALE

       None.

FUTURE DIRECTIONS

       None.

SEE ALSO

       mblen(), mbtowc(), mbstowcs(), wctomb()

       The Base Definitions volume of POSIX.1‐2008, <stdlib.h>

COPYRIGHT

       Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1, 2013 Edition,
       Standard  for  Information Technology -- Portable Operating System Interface (POSIX), The Open Group Base
       Specifications Issue 7, Copyright (C) 2013 by the Institute of Electrical and Electronics Engineers,  Inc
       and  The  Open Group.  (This is POSIX.1-2008 with the 2013 Technical Corrigendum 1 applied.) In the event
       of any discrepancy between this version and the original IEEE and The Open Group Standard,  the  original
       IEEE and The Open Group Standard is the referee document. The original Standard can be obtained online at
       http://www.unix.org/online.html .

       Any typographical or formatting errors that appear in this page are most likely to have  been  introduced
       during   the   conversion  of  the  source  files  to  man  page  format.  To  report  such  errors,  see
       https://www.kernel.org/doc/man-pages/reporting_bugs.html .