Socket.Send throw exception with 'The descriptor is not a socket'

[ctacke]

Meadow F7 Project Lab
OS v 1.10.0.2

MeadowSocketSend Test application attached

I have a pair of very simple applications, a client and sender that use a Socket for communication.
The "Client" app runs on a PC, accepts and listens for a sender to attach.
The "Sender" connects, and sends a simple text message.

This works fine on a desktop machine.
On the Meadow, the call to Send throw an exception with the message "The descriptor is not a socket"

[jbeenes]

We have been struggling with WebSockets on Meadow too, using System.Net.WebSockets. Did you test with this aswell?

In our search to get our test working I came across this link, where the part under Remarks made me think this might never work on something other then Windows. Do you agree?

We made it work eventually using a library called SocketSharp.

Ps. I have not tested it on Linux btw.

[djaus2]

I am currently experiencing a related problem "The descriptor is not a socket".
My code is similar to @ctacke code as above.

Situation:

• TCP Service running on an Arduino device
• Client that connects to it implemented as a .NET Class library
• .NET 6 or 8 and .NET Standard 2.1
• Client = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
  • Also tried as TCPClient with same result.
• All works OK from desktop as 2 apps
  • .NET Console app with .NET Class
  • Blazor App with .NET Class
• In Meadow context ProjectLabs device
  • Using .NET Standard version of Library
  • Can connect
  • Get "The descriptor is not a socket" error when sending to service
  • Of note is that the Client.Available property returns that error.
• Can run OK as Meadow.Windows app on desktop using either .NET or .NET Standard class library.

I did use while (Client.Available == 0) ; which would obviously fail if .Available is errant. Replaced it with a several second wait and app hung.

Have drilled into this a bit on Slack: https://wildernesslabspublic.slack.com/archives/CB9BW8HQE/p1712460726231349

[djaus2]

Have posted Softata with MeadowLabs app version on GitHub: djaus2/Soft-ata
MeadowLab app generates this error.

[duduita]

The core of this issue lies in the Socket.Available property, which relies on a native function that is currently unsupported by our operating system version. The OS rebase, expected in the coming months, should definitively resolve this problem.

As a temporary solution, the Socket.Available property will return 1 when there are bytes ready to be read and 0 when there aren't. While this workaround may not provide exact data availability, it serves as a reliable indicator of whether the socket contains readable data, and also eliminates the The descriptor is not a socket exception occurrence.

[djaus2]

Thanks for the update. David Jones Get Outlook for Android<https://aka.ms/AAb9ysg>

…

________________________________ From: Eduardo Menezes ***@***.***> Sent: Tuesday, April 23, 2024 8:55:48 AM To: WildernessLabs/Meadow_Issues ***@***.***> Cc: David Jones (MVP) ***@***.***>; Comment ***@***.***> Subject: Re: [WildernessLabs/Meadow_Issues] Socket.Send throw exception with 'The descriptor is not a socket' (Issue #590) The core of this issue lies in the Socket.Available property, which relies on a native function that is currently unsupported by our operating system version. The OS rebase, expected in the coming months, should definitively resolve this problem. As a temporary solution, the Socket.Available property will return 1 when there are bytes ready to be read and 0 when there aren't. While this workaround may not provide exact data availability, it serves as a reliable indicator of whether the socket contains readable data. — Reply to this email directly, view it on GitHub<#590 (comment)>, or unsubscribe<https://github.com/notifications/unsubscribe-auth/AC7U2EIXBEXFTFXPD7EVSLLY6WIPJAVCNFSM6AAAAABF6ZJ3VOVHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZDANZRGA4DMNRWGE>. You are receiving this because you commented.Message ID: ***@***.***>

[ctacke]

Fixed in 1.11