if (isalpha (codeset[cnt]))
if (isalpha ((unsigned char) codeset[cnt]))
_nl_normalize_codeset (codeset, name_len)     const char *codeset;     size_t name_len;{  int len = 0;  int only_digit = 1;  char *retval;  char *wp;  size_t cnt;  for (cnt = 0; cnt < name_len; ++cnt)    if (isalnum (codeset[cnt]))      {	++len;	if (isalpha (codeset[cnt]))	  only_digit = 0;      }  retval = (char *) malloc ((only_digit ? 3 : 0) + len + 1);  if (retval != NULL)    {      if (only_digit)	wp = stpcpy (retval, "iso");      else	wp = retval;      for (cnt = 0; cnt < name_len; ++cnt)	if (isalpha (codeset[cnt]))	  *wp++ = tolower (codeset[cnt]);	else if (isdigit (codeset[cnt]))	  *wp++ = codeset[cnt];      *wp = '\0';    }  return (const char *) retval;}