[Mac] Added CFRetain binding

diff --git a/Source/OpenTK/Platform/MacOS/Quartz/CoreFoundation.cs b/Source/OpenTK/Platform/MacOS/Quartz/CoreFoundation.cs
index 6b5c881..262fd7f 100644 (file)
--- a/Source/OpenTK/Platform/MacOS/Quartz/CoreFoundation.cs
+++ b/Source/OpenTK/Platform/MacOS/Quartz/CoreFoundation.cs
@@ -113,6 +113,9 @@ namespace OpenTK.Platform.MacOS.Carbon
         internal static extern IntPtr CFDictionaryGetValue(IntPtr theDictionary, IntPtr theKey);
 
         [DllImport(appServices)]
+        internal static extern IntPtr CFRetain(CFTypeRef cf);
+
+        [DllImport(appServices)]
         internal static extern void CFRelease(CFTypeRef cf);
 
         // this mirrors the definition in CFString.h.