NETMQ fails on Linux: Windows-specific control codes and is not supported on this platform.

[maxima120]

Environment

NetMQ Version:   4.0.1.6
Operating System: CentOS8
.NET Version:  5.0.1

Expected behaviour

should work as promised on .NET Core platform

Actual behaviour

Fails

Steps to reproduce the behaviour

try to connect to a NETMQ server from ASP.NET Core app

Unhandled exception. System.PlatformNotSupportedException: Socket.IOControl handles Windows-specific control codes and is not supported on this platform.
   at System.Net.Sockets.SocketPal.WindowsIoctl(SafeSocketHandle handle, Int32 ioControlCode, Byte[] optionInValue, Byte[] optionOutValue, Int32& optionLength)
   at System.Net.Sockets.Socket.IOControl(Int32 ioControlCode, Byte[] optionInValue, Byte[] optionOutValue)
   at System.Net.Sockets.Socket.IOControl(IOControlCode ioControlCode, Byte[] optionInValue, Byte[] optionOutValue)
   at AsyncIO.DotNet.NativeSocket.IOControl(IOControlCode ioControlCode, Byte[] optionInValue, Byte[] optionOutValue)
   at NetMQ.Core.Transports.Tcp.TcpConnector.OutCompleted(SocketError socketError, Int32 bytesTransferred)
   at NetMQ.Core.IOObject.OutCompleted(SocketError socketError, Int32 bytesTransferred)
   at NetMQ.Core.Utils.Proactor.Loop()
   at System.Threading.ThreadHelper.ThreadStart_Context(Object state)
   at System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state)

[daconglee]

up

[wjrogers]

FYI, support for TCP keep-alive was added to SetSocketOption() in .NET Core 3.0. Unfortunately, the new option names were never added to .NET Standard, so supporting TCP keep-alive on Linux would require adding a netcoreapp3.1 (or newer) target to NetMQ. Then, code similar to this could be introduced to TcpConnector and TcpListener:

#if NETCOREAPP3_1
// for .NET (Core) with the new socket options, use them (N.B. SetSocketOption units are seconds, not milliseconds)
if (m_options.TcpKeepaliveIdle != -1)
    m_s.SetSocketOption(SocketOptionLevel.Tcp, SocketOptionName.TcpKeepAliveTime, m_options.TcpKeepaliveIdle / 1000);
if (m_options.TcpKeepaliveIntvl != -1)
    m_s.SetSocketOption(SocketOptionLevel.Tcp, SocketOptionName.TcpKeepAliveInterval, m_options.TcpKeepaliveIntvl / 1000);
#else
// ... retain existing code path for Windows / .NET Framework
#endif

[dnovhorodov]

Any news on the issue? When a fix could be expected?
Running 4.0.1.6 version of NetMQ with netcoreapp3.1 is failing

[RWander]

up!

[RWander]

Running with net6.0 is failing as well!

[danielsilva-iq]

up!

[SpiritDogstar]

bump

[chrbauer]

I added wjrogers suggestion to a branch. For simplicity only .net8 is now supported:

https://github.com/chrbauer/netmq/tree/net8/tcp-keepalive-linux

It compiles, all tests are green. All nugets are up to date.

[chrbauer]

What do we need to do for an acceptable pull request?

1. There is a dedicided branch only for .net8 version. (This is currently the solution in the patch from the previous comment).
2. We replace netstandard2.1 by netcoreapp3.1 and set TCP KeepAlive with #if NETCOREAPP_3_1
3. Like 2, but we keep the netstandard2.1 target

[chrbauer]

Hm. netcoreapp3.1 is not working, but net8.0.
==> #1120