Add RuntimeInformation.RuntimeIdentifier

[eerhardt]

This value returns the Runtime Identifier (RID) of the current machine.

Contributes to #26780

Most of the tests are disabled because we use an old host to run our tests. When we update to a host with the new code, the tests can be enabled. I'll keep #26780 open until the tests are enabled.

[Dotnet-GitSync-Bot]

Note regarding the new-api-needs-documentation label:

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[jkotas]

Thanks

[ViktorHofer]

@eerhardt @rainersigwald can we make that property readable from msbuild as a property function?

• By default, you can only call certain members on certain types – selected to be free of side-effects. Here’s the full list:

from https://devblogs.microsoft.com/visualstudio/msbuild-property-functions/. Sounds to me like we need to "white-list" that property? That information could be outdated as I see that we are reading other properties from RuntimeInformation already:

runtime/src/libraries/Directory.Build.props

Line 34 in d307659

<HostArch>$([System.Runtime.InteropServices.RuntimeInformation]::ProcessArchitecture.ToString().ToLowerInvariant)</HostArch>

[eerhardt]

can we make that property readable from msbuild as a property function?

It is already possible today (since this property is on RuntimeInformation):

  <PropertyGroup>
    <MyRid>$([System.Runtime.InteropServices.RuntimeInformation]::RuntimeIdentifier)</MyRid>
  </PropertyGroup>

  <Target Name="PostBuild"
          AfterTargets="Build">
    <Message Text="Current RID: $(MyRid)" Importance="high" />
  </Target>

On my machine outputs:

  Current RID: win10-x64

However, note that this will only work from MSBuild running on .NET 5 and above, since this API is only available there. It won't work on .NET Core 3.x, nor will it work on MSBuild running on .NET Framework.

[ViktorHofer]

Great, thanks!