nit: formatting

nit: formatting

nit: formatting

nit: formatting

The linter is not happy with this change. You can do `git clang-format HEAD~<N>` to format `<N>` commits. `<N>` is optional when `N == 1`. For example, `git clang-format HEAD~5` would format that past 5 commits.

you can't use `SYS_pipe` for `SYS_pipe2` since it doesn't respect the `flags` argument. We only define one syscall in terms of another when it can completely mimic the behavior.

Missing new line at the end of the file?

Note that this is currently failing in presubmit. ``` /var/lib/buildkite-agent/builds/linux-56-59b8f5d88-6mhbj-1/llvm-project/github-pull-requests/libc/test/src/unistd/pipe2_test.cpp:54: FAILURE Failed to match LIBC_NAMESPACE::pipe2(pipefd, invalidflags) against Fails(EINVAL). Expected return value to be equal to -1 but got -22. ``` This is because upon failure, the kernel will return `-EINVAL` to userspace, so your existing logic is returning that, too. Upon failure, we should set the return value of `pipe2` to `-1`.

This include should be unnecessary.

```suggestion if (ret >= 0) return ret; libc_errno = -ret; return -1; ``` (updated)

Put these 3 includes together with no extra new lines, then sort.

@michaelrj-google can you check these types? This is slightly different than how you chose to define an `int [2]` in https://github.com/llvm/llvm-project/pull/84587/files.