MSBuild cannot detect MacOSX

[takuya-takeuchi]

Summary of your issue

In build/DlibDotNet.Native.props, $(OS) does not work on MacOSX.
dotnet/msbuild#538

It does not occur errror.
Because *.so and *.dylib will be copied porperly.
But *.so files are extra and it consumes disk space.

Environment

On MacOSX.

[valerysntx]

Consider using $([MSBuild]::IsOsPlatform("osx"))) put into Condition= attribute, like

 <PropertyGroup>
    <OsEnvironment Condition="$([MSBuild]::IsOSPlatform('windows'))">windows</OsEnvironment>
    <OsEnvironment Condition="$([MSBuild]::IsOSPlatform('linux'))">linux</OsEnvironment>
    <OsEnvironment Condition="$([MSBuild]::IsOSPlatform('osx'))">osx</OsEnvironment>

    <OsUnixLike>false</OsUnixLike>
    <OsUnixLike Condition="$([MSBuild]::IsOsUnixLike())">true</OsUnixLike>

taken from Directory.Build.props in Microsoft/msbuild repo

Also, here is much longer version, found around

   '$([System.Runtime.InteropServices.RuntimeInformation]::IsOSPlatform(
                $([System.Runtime.InteropServices.OSPlatform]::OSX))
    )' 

[takuya-takeuchi]

Close by e096e96