Added P/Invoke helpers for unmanaged-unmanaged memory copies.

build/premake4.lua

@@ -27,6 +27,9 @@ solution "CppSharp"
   configuration "vs2012"
     framework "4.0"
 
+  configuration "windows"
+    defines { "WINDOWS" }
+
   configuration {}
     
   group "Examples"

src/Runtime/Helpers.cs

@@ -0,0 +1,15 @@
+using System;
+using System.Runtime.InteropServices;
+
+namespace CppSharp.Runtime
+{
+    public static class Helpers
+    {
+#if WINDOWS
+        [DllImport("msvcrt.dll", EntryPoint = "memcpy", CallingConvention = CallingConvention.Cdecl)]
+#else
+        [DllImport("libc", EntryPoint = "memcpy")]
+#endif
+        public static extern IntPtr memcpy(IntPtr dest, IntPtr src, UIntPtr count);
+    }
+}