Rev3739, Fix atomicWrite of non existent file

src/Config.py

@@ -13,7 +13,7 @@ class Config(object):
 
     def __init__(self, argv):
         self.version = "0.6.4"
-        self.rev = 3738
+        self.rev = 3739
         self.argv = argv
         self.action = None
         self.pending_changes = {}

src/util/helper.py

@@ -20,9 +20,10 @@ def atomicWrite(dest, content, mode="w"):
             os.fsync(f.fileno())
         if os.path.isfile(dest + "-tmpold"):  # Previous incomplete write
             os.rename(dest + "-tmpold", dest + "-tmpold-%s" % time.time())
-        os.rename(dest, dest + "-tmpold")
+        if os.path.isfile(dest):  # Rename old file to -tmpold
+            os.rename(dest, dest + "-tmpold")
         os.rename(dest + "-tmpnew", dest)
-        os.unlink(dest + "-tmpold")
+        os.unlink(dest + "-tmpold")  # Remove old file
         return True
     except Exception, err:
         from Debug import Debug