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/*

FUNCTION

<>---minimal wide char string to multibyte string converter

INDEX

	wcstombs

ANSI_SYNOPSIS

	#include 

	size_t wcstombs(char *restrict <[s]>, const wchar_t *restrict <[pwc]>, size_t <[n]>);

TRAD_SYNOPSIS

	#include 

	size_t wcstombs(<[s]>, <[pwc]>, <[n]>)

	char *<[s]>;

	const wchar_t *<[pwc]>;

	size_t <[n]>;

DESCRIPTION

When _MB_CAPABLE is not defined, this is a minimal ANSI-conforming

implementation of <>.  In this case,

all wide-characters are expected to represent single bytes and so

are converted simply by casting to char.

When _MB_CAPABLE is defined, this routine calls <<_wcstombs_r>> to perform

the conversion, passing a state variable to allow state dependent

decoding.  The result is based on the locale setting which may

be restricted to a defined set of locales.

RETURNS

This implementation of <> returns <<0>> if

<[s]> is <> or is the empty string;

it returns <<-1>> if _MB_CAPABLE and one of the

wide-char characters does not represent a valid multi-byte character;

otherwise it returns the minimum of: <> or the

number of bytes that are transferred to <>, not including the

nul terminator.

If the return value is -1, the state of the <> string is

indeterminate.  If the input has a length of 0, the output

string will be modified to contain a wchar_t nul terminator if

<> > 0.

PORTABILITY

<> is required in the ANSI C standard.  However, the precise

effects vary with the locale.

<> requires no supporting OS subroutines.

*/

#ifndef _REENT_ONLY

#include 

#include 

#include 

size_t

_DEFUN (wcstombs, (s, pwcs, n),

        char          *__restrict s    _AND

        const wchar_t *__restrict pwcs _AND

        size_t         n)

{

#ifdef _MB_CAPABLE

  mbstate_t state;

  state.__count = 0;

  return _wcstombs_r (_REENT, s, pwcs, n, &state);

#else /* not _MB_CAPABLE */

  int count = 0;

  if (n != 0) {

    do {

      if ((*s++ = (char) *pwcs++) == 0)

	break;

      count++;

    } while (--n != 0);

  }

  return count;

#endif /* not _MB_CAPABLE */

}

#endif /* !_REENT_ONLY */