Detect mono using PlatformAbstractions

src/Microsoft.AspNet.Server.Kestrel/Networking/Libuv.cs

@@ -12,7 +12,7 @@ namespace Microsoft.AspNet.Server.Kestrel.Networking
         {
             IsWindows = PlatformApis.IsWindows;
 
-            var isDarwinMono = !IsWindows && PlatformApis.IsDarwin;
+            var isDarwinMono = PlatformApis.IsDarwin && PlatformApis.IsMono;
 
             if (isDarwinMono)
             {

src/Microsoft.AspNet.Server.Kestrel/Networking/PlatformApis.cs

@@ -3,6 +3,7 @@
 
 using System;
 using System.Runtime.InteropServices;
+using Microsoft.Extensions.PlatformAbstractions;
 
 namespace Microsoft.AspNet.Server.Kestrel.Networking
 {
@@ -24,12 +25,16 @@ namespace Microsoft.AspNet.Server.Kestrel.Networking
                 IsDarwin = string.Equals(GetUname(), "Darwin", StringComparison.Ordinal);
             }
 #endif
+
+            IsMono = PlatformServices.Default.Runtime.RuntimeType == "Mono";
         }
 
         public static bool IsWindows { get; }
 
         public static bool IsDarwin { get; }
 
+        public static bool IsMono { get; }
+
         [DllImport("libc")]
         static extern int uname(IntPtr buf);
 

src/Microsoft.AspNet.Server.Kestrel/project.json

@@ -8,6 +8,7 @@
   "dependencies": {
     "Microsoft.AspNet.Hosting": "1.0.0-*",
     "Microsoft.Extensions.Logging.Abstractions": "1.0.0-*",
+    "Microsoft.Extensions.PlatformAbstractions": "1.0.0-*",
     "System.Numerics.Vectors": "4.1.1-*",
     "Microsoft.StandardsPolice": {
       "version": "1.0.0-*",