go/doc/next/6-stdlib/99-minor/os/15388.md

On Windows, [NewFile] supports overlapped (a.k.a non-blocking) file handles even
when the handle can't be added to the Go runtime I/O Completion Port (IOCP), normally
because it is already attached to another IOCP. The I/O operations will be performed in
a blocking manner instead of using the Go runtime IOCP.
Particularly, this means that is now possible to reliably pass overlapped named pipes and
sockets to a Go process standard input, output, and error.
os,internal/poll: support I/O on overlapped handles not added to the poller Calling syscall.ReadFile and syscall.WriteFile on overlapped handles always need to be passed a valid *syscall.Overlapped structure, even if the handle is not added to a IOCP (like the Go runtime poller). Else, the syscall will fail with ERROR_INVALID_PARAMETER. We also need to handle ERROR_IO_PENDING errors when the overlapped handle is not added to the poller, in which case we need to block until the operation completes. Previous CLs already added support for overlapped handles to the poller, mostly to keep track of the file offset independently of the file pointer (which is not supported for overlapped handles). Fixed #15388. Updates #19098. Change-Id: I2103ab892a37d0e326752ae8c2771a43c13ba42e Reviewed-on: https://go-review.googlesource.com/c/go/+/661795 Auto-Submit: Quim Muntal <quimmuntal@gmail.com> LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: Carlos Amedee <carlos@golang.org> Reviewed-by: Damien Neil <dneil@google.com> 2025-03-31 11:43:12 +02:00			`On Windows, [NewFile] supports overlapped (a.k.a non-blocking) file handles even`
			`when the handle can't be added to the Go runtime I/O Completion Port (IOCP), normally`
			`because it is already attached to another IOCP. The I/O operations will be performed in`
			`a blocking manner instead of using the Go runtime IOCP.`
			`Particularly, this means that is now possible to reliably pass overlapped named pipes and`
			`sockets to a Go process standard input, output, and error.`