text: #include <wchar.h>
  #include <stdlib.h>
  #include <stdio.h>
  #include <reent.h>
  #include <string.h>
  #include "local.h"
  
  wint_t
  btowc (int c)
  {
    mbstate_t mbs;
    int retval = 0;
    wchar_t pwc;
    unsigned char b;
  
    if (c == EOF)
      return WEOF;
  
    b = (unsigned char)c;
  
    /* Put mbs in initial state. */
    memset (&mbs, '\0', sizeof (mbs));
  
    _REENT_CHECK_MISC(_REENT);
  
    retval = __mbtowc (_REENT, &pwc, (const char *) &b, 1,
  		     __locale_charset (), &mbs);
  
    if (retval != 0 && retval != 1)
      return WEOF;
  
    return (wint_t)pwc;
  }
  