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

[Nick Desaulniers via libc-commits]

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@@ -0,0 +1,33 @@
+//===-- Linux implementation of pipe --------------------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#include "src/unistd/pipe.h"
+
+#include "src/__support/OSUtil/syscall.h" // For internal syscall function.
+#include "src/__support/common.h"
+#include "src/errno/libc_errno.h"
+#include <sys/syscall.h> // For syscall numbers.
+
+namespace LIBC_NAMESPACE {
+
+LLVM_LIBC_FUNCTION(int, pipe, (int pipefd[2])) {
+#ifdef SYS_pipe
+  int ret = LIBC_NAMESPACE::syscall_impl<int>(SYS_pipe,
+                                              reinterpret_cast<long>(pipefd));
+#elif defined(SYS_pipe2)
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nickdesaulniers wrote:

again, if pipe2 is newer, than shouldn't we be checking for then using that first? man page says linux 2.6.27 (ancient)

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