Thread: wrong wrong with my xor function?

Code:

char *Encode(char *str, char *key)
{
	unsigned int i, j;

	for (i = 0; i < strlen(str); i++)
	{
		for (j = 0; j < strlen(key); j++)
			str[i] ^= key[j];

		str[i] = ~ str[i];
	}

	return str;
}

to use i do

char *WSAStartupChar ="\xFC\xF8\xEA\xF8\xDF\xCA\xD9\xDF\xDE\xDB"; //WSAStartup
char *WSAStartupEncode = Encode(WSAStartupChar,key);
char *WSAStarupDecode = Encode(WSAStartupEncode,key);
WSAStartup = (WSAS)GetProcAddress(ws2_32_dll,WSAStarupDecode);

whats can the prob be ,