Fix bug of detect usb, if they are absent.

pym/cl_fill_install.py

@@ -90,9 +90,12 @@ class fillVars(object, glob_attr):
 
     def get_os_device_hash(self):
         diskIdPath = '/dev/disk/by-id'
-        usbdevices = \
-            map(lambda x: readlink(pathjoin(diskIdPath,x)).rpartition('/')[2],
-            filter(lambda x: x.startswith('usb-'),listdir(diskIdPath)))
+        if pathexists(diskIdPath):
+            usbdevices = \
+             map(lambda x: readlink(pathjoin(diskIdPath,x)).rpartition('/')[2],
+             filter(lambda x: x.startswith('usb-'),listdir(diskIdPath)))
+        else:
+            usbdevices = []
         reWrongDevice = re.compile("|".join(['sr','fd','ram','loop']))
         devices = filter( lambda x: not reWrongDevice.search(x),
                         listdir('/sys/block'))