Obsolete Socket.UseOnlyOverlappedIO

[antonfirsov]

Background and Motivation

This property it is only meaningful on .NET Framework where it functions as a socket-level switch between IOCP and Win32 event based overlapped IO.

.NET (Core) Windows sockets are entirely IOCP-based, and the concept of "overlapped IO" does not exist on other platforms, therefore the property contains empty logic, and there is no chance we will ever implement it. To avoid confusion, I suggest to obsolete and hide it it together with the related flag in SocketInformationOptions.

Proposed API

public class Socket
{
+   [Obsolete]
+   [EditorBrowsable(EditorBrowsableState.Never)]
    public bool UseOnlyOverlappedIO { get; set; }
}

public enum SocketInformationOptions
{
    NonBlocking = 1,
    Connected = 2,
    Listening = 4,
+   [Obsolete]
+   [EditorBrowsable(EditorBrowsableState.Never)]
    UseOnlyOverlappedIO = 8,
}

Risks

Breaking /warnaserror builds when porting to .NET 6. (Which may actually prevent runtime failures.)

[ghost]

Tagging subscribers to this area: @dotnet/ncl
See info in area-owners.md if you want to be subscribed.

Issue Details

---

Background and Motivation

This property it is only meaningful on .NET Framework where it functions as a ocket-level switch between IOCP and Win32 event based async IO.

.NET (Core) Windows sockets are entirely IOCP-based, and the concept of "overlapped IO" does not exist on other platforms, therefore the property contains empty logic, and there is no chance we will ever implement it. To avoid confusion, I suggest to obsolete it.

Proposed API

public class Socket
{
+   [Obsolete]
    public bool UseOnlyOverlappedIO { get; set; }
}

Risks

Breaking /warnaserror builds when porting to .NET 6. (Which may actually prevent runtime failures.)

Author:	antonfirsov
Assignees:	-
Labels:	api-suggestion, area-System.Net.Sockets, untriaged
Milestone:	-

[Wraith2]

Is it also worth marking it as non browsable?

[antonfirsov]

Is it also worth marking it as non browsable?

In my opinion - yes, so updated the proposal.

[karelz]

Triage: We agree, it is no-op on .NET Core, let's obsolete it.

[terrajobst]

Video

• Looks good
• It feels over-engineered to add a diagnostic ID to this obsoletion

namespace System.Net.Sockets
{
    public partial class Socket
    {
        [Obsolete]
        [EditorBrowsable(EditorBrowsableState.Never)]
        public bool UseOnlyOverlappedIO { get; set; }
    }
    public partial enum SocketInformationOptions
    {
        [Obsolete]
        [EditorBrowsable(EditorBrowsableState.Never)]
        UseOnlyOverlappedIO = 8,
    }
}