static int str_is_utf8(int code)
{
	return code < 0x0020 || code > 0x007e;
}

static void str_utf8_slug(const char *pStrning, char *pSlugged, int SizeOfSlugged)
{
	int code;
	int i = 0;

	while(*pStrning)
	{
		code = str_utf8_decode(&pStrning);
		if(str_is_utf8(code))
			pSlugged[i] = '?';
		char aBuf[16];
		str_utf8_encode(aBuf, code);
		pSlugged[i] = aBuf[0] == '\0' ? '?' : aBuf[0];
		i++;
		if(i >= SizeOfSlugged)
			break;
	}
	pSlugged[i] = '\0';
}