How to debug?

[bwjohns4]

Is it possible to put log statements in the background task that's being called by the OS/Vpn? I'm building my own vpn application and need to be able to see into the VpnPlugin client that's running on the background task like in this example.

[ysc3839]

I don't know. I suggest you ask author of YtFlow: @bdbai. He is experienced on this.

[bdbai]

I am not an expert in Win32 programming as well. AFAIK basically debugging/logging techniques for UWP apps (or even Win32 apps) in general also apply to VPN plugins. Here are some options that you might want to consider:

• Send debugging logs to Visual Studio debugger using OutputDebugString.
• Write logs to a file where your app has access to, like ApplicationData.LocalFolder.
• Use TCP/UDP/WebSocket or whatever socket to send and receive logs. Be careful with loopback communication limitations.
• Use Windows.Networking.Vpn.VpnChannel.LogDiagnosticMessage.
• Use ETW logging. See this example: https://github.com/microsoft/Windows-universal-samples/blob/main/Samples/Logging/README.md .