NetworkInterface.GetAllNetworkInterfaces() on Android leads to FileNotFoundException ('/etc/resolv.conf')

Description

Hi,

we tried to port our Xamarin.Forms app to MAUI and encountered a bug.

When calling System.Net.NetworkInformation.NetworkInterface.GetAllNetworkInterfaces() we get an FileNotFoundException On Windows this works.

Callstack {System.Net.NetworkInformation.NetworkInformationException (0x80004005): Success at System.Net.NetworkInformation.LinuxNetworkInterface.GetLinuxNetworkInterfaces() at System.Net.NetworkInformation.NetworkInterfacePal.GetAllNetworkInterfaces() at System.Net.NetworkInformation.NetworkInterface.GetAllNetworkInterfaces() at Busmonitor.MAUI.MainPageViewModel.Discover() in C:\git\Busmonitor\Busmonitor.MAUI\ViewModels\MainPageViewModel.cs:line 70}

Best regards

Steps to Reproduce

1. In MAUI Template add NetworkInterface.GetAllNetworkInterfaces() to Button Handler
2. On Executing the code a file System.IO.FileNotFoundException: ‘Could not find file ‘/etc/resolv.conf’.’ get thrown

Version with bug

Preview 10 (current)

Last version that worked well

Preview 10 (current)

Affected platforms

Android

Affected platform versions

Android 10

Did you find any workaround?

no

Relevant log output

No response

[dos-ise]

https://github.com/dotnet/runtime/pull/62780

This seems to fix the problem when merged.

[dos-ise]

After looking at the code you linked I think there is no way this code could ever run on android. The implementation completely relies on parsing the resolv.conf file. Which is not available on android. I think this it is also not available on some linux distros and I am not sure if this is available on iOS.

[https://github.com/dotnet/runtime/blob/b201a16e1a642f9532c8ea4e42d23af8f4484a36/src/libraries/System.Net.NetworkInformation/src/System/Net/NetworkInformation/LinuxNetworkInterface.cs#L56]

The mono implementation on the other hand seems much better here. [https://github.com/mono/mono/blob/bdd772531d379b4e78593587d15113c37edd4a64/mcs/class/System/System.Net.NetworkInformation/LinuxNetworkInterface.cs#L64]