[libc] [llvm] [libc] add remaining epoll functions, pipe (PR #84587)

[Nick Desaulniers via llvm-commits]

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@@ -0,0 +1,38 @@
+//===-- Macros defined in sys/epoll.h header file -------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_LIBC_MACROS_LINUX_SYS_EPOLL_MACROS_H
+#define LLVM_LIBC_MACROS_LINUX_SYS_EPOLL_MACROS_H
+
+#include "llvm-libc-macros/linux/fcntl-macros.h"
+
+// TODO: Do we need to define these?
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nickdesaulniers wrote:

`<linux/eventpoll.h>`?

https://github.com/llvm/llvm-project/pull/84587