UnityEditor.BuildPipeline.GetMonoLibDirectory C# (CSharp) Method

        internal static extern string GetMonoLibDirectory(BuildTarget target);
        [MethodImpl(MethodImplOptions.InternalCall)]

 public static string GetMonoPath(BuildTarget buildTarget)
 {
     return(BuildPipeline.GetMonoLibDirectory(buildTarget) + Path.PathSeparator + ".");
 }