Restore support for Microsoft VC6 compiler.
Some functions in the msvcrt module are skipped,
and socket.ioctl is enabled only when using a more recent Platform SDK.
(and yes, there are still companies that use a 10-years old compiler)
diff --git a/Modules/socketmodule.c b/Modules/socketmodule.c
index e956831..e4c8ac8 100644
--- a/Modules/socketmodule.c
+++ b/Modules/socketmodule.c
@@ -2805,7 +2805,7 @@
Shut down the reading side of the socket (flag == SHUT_RD), the writing side\n\
of the socket (flag == SHUT_WR), or both ends (flag == SHUT_RDWR).");
-#ifdef MS_WINDOWS
+#if defined(MS_WINDOWS) && defined(SIO_RCVALL)
static PyObject*
sock_ioctl(PySocketSockObject *s, PyObject *arg)
{
@@ -2858,7 +2858,7 @@
METH_NOARGS, getsockname_doc},
{"getsockopt", (PyCFunction)sock_getsockopt, METH_VARARGS,
getsockopt_doc},
-#ifdef MS_WINDOWS
+#if defined(MS_WINDOWS) && defined(SIO_RCVALL)
{"ioctl", (PyCFunction)sock_ioctl, METH_VARARGS,
sock_ioctl_doc},
#endif