NewFile was recently updated (in CL 668195) to detect whether the
handle is a socket or not. This special case is not really necessary,
given that socket handles can be used as if they were normal file
handles on all functions supported by os.File (see https://learn.microsoft.com/en-us/windows/win32/winsock/socket-handles-2).
Not only is not necessary, but is can also be problematic, as there is
no way to reliably detect whether a handle is a socket or not. For
example, the test failure reported in #73630 is caused by a named pipe
wrongly detected as a socket.
This aligns with the Unix NewFile behavior of returning an os.File that
identifies itself as a file handle even if it is a socket. This makes
os.File.Close to always return os.ErrClosed in case of multiple calls
rather than sometimes returning "use of closed network connection".
Updates #10350.
Fixes #73630.
Change-Id: Ia8329783d5c8ef6dac34ef69ed1ce9d2a9862e11
Reviewed-on: https://go-review.googlesource.com/c/go/+/671455
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: Michael Knyszek <mknyszek@google.com> Reviewed-by: Damien Neil <dneil@google.com>