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

[Nick Desaulniers via llvm-commits]

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@@ -0,0 +1,25 @@
+//===-- Implementation header for epoll_ctl function ------------*- C++ -*-===//
+//
+// 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_SRC_SYS_EPOLL_EPOLL_CTL_H
+#define LLVM_LIBC_SRC_SYS_EPOLL_EPOLL_CTL_H
+
+// TODO: Use this include once the include headers are also using quotes.
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nickdesaulniers wrote:

What's the issue preventing this?

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