_overlapped_BindLocal_impl() exception message is not helpful

[dlech]

Bug report

Bug description:

When calling loop.sock_connect() on Windows, it calls into _overlapped_BindLocal_impl().

cpython/Modules/overlapped.c

Lines 539 to 569 in b6d8aa4

	static PyObject *
	_overlapped_BindLocal_impl(PyObject *module, HANDLE Socket, int Family)
	/*[clinic end generated code: output=edb93862697aed9c input=a0e7b5c2f541170c]*/
	{
	BOOL ret;
	if (Family == AF_INET) {
	struct sockaddr_in addr;
	memset(&addr, 0, sizeof(addr));
	addr.sin_family = AF_INET;
	addr.sin_port = 0;
	addr.sin_addr.S_un.S_addr = INADDR_ANY;
	ret = bind((SOCKET)Socket, (SOCKADDR*)&addr, sizeof(addr))
	!= SOCKET_ERROR;
	} else if (Family == AF_INET6) {
	struct sockaddr_in6 addr;
	memset(&addr, 0, sizeof(addr));
	addr.sin6_family = AF_INET6;
	addr.sin6_port = 0;
	addr.sin6_addr = in6addr_any;
	ret = bind((SOCKET)Socket, (SOCKADDR*)&addr, sizeof(addr))
	!= SOCKET_ERROR;
	} else {
	PyErr_SetString(PyExc_ValueError, "expected tuple of length 2 or 4");
	return NULL;
	}
	if (!ret)
	return SetFromWindowsErr(WSAGetLastError());
	Py_RETURN_NONE;
	}

If the socket is not an AF_INET or AF_INET6 socket (for example an AF_BLUETOOTH socket), a ValueError is raised with the message: "expected tuple of length 2 or 4". This makes no sense. The actual problem is that the function only supports the two IP families. The error message should explain this.

CPython versions tested on:

3.14

Operating systems tested on:

Windows

Linked PRs

• gh-144493: Improve error message in _overlapped.BindLocal() #144495