Fix build issues on OSX 10.6 (issue 6802)
diff --git a/Lib/plat-mac/applesingle.py b/Lib/plat-mac/applesingle.py
index f6c605f..13962f6 100644
--- a/Lib/plat-mac/applesingle.py
+++ b/Lib/plat-mac/applesingle.py
@@ -119,8 +119,13 @@
     if not hasattr(infile, 'read'):
         if isinstance(infile, Carbon.File.Alias):
             infile = infile.ResolveAlias()[0]
-        if isinstance(infile, (Carbon.File.FSSpec, Carbon.File.FSRef)):
-            infile = infile.as_pathname()
+
+        if hasattr(Carbon.File, "FSSpec"):
+            if isinstance(infile, (Carbon.File.FSSpec, Carbon.File.FSRef)):
+                infile = infile.as_pathname()
+        else:
+            if isinstance(infile, Carbon.File.FSRef):
+                infile = infile.as_pathname()
         infile = open(infile, 'rb')
 
     asfile = AppleSingle(infile, verbose=verbose)