--- /dev/null
+/*
+ * Copyright 2016 Facebook, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#pragma once
+
+// This file only exists because without it there would be
+// a circular dependency between SysUio.h, Sockets.h, and Unistd.h
+#ifndef _WIN32
+#include <sys/uio.h>
+#else
+#include <stdlib.h>
+
+#define UIO_MAXIOV 16
+#define IOV_MAX UIO_MAXIOV
+
+struct iovec {
+ void* iov_base;
+ size_t iov_len;
+};
+#endif