NFD

Environment: OSX 10.9

Steps to reproduce:

1. Register some prefix for udp4 multicast face:

   [cawka@cawka-mac NFD (master)]$ nfd-status -f
   Faces:
     faceid=1 remote=internal:// local=internal:// counters={in={0i 29d} out={19i 0d}}
     faceid=2 remote=udp4://224.0.23.170:56363 local=udp4://10.0.0.2:56363 counters={in={0i 0d} out={0i 0d}}
     faceid=3 remote=udp4://224.0.23.170:56363 local=udp4://127.0.0.1:56363 counters={in={0i 0d} out={0i 0d}}
     faceid=4 remote=ether://[01:00:5e:00:17:aa] local=dev://bridge0 counters={in={0i 0d} out={0i 0d}}
     faceid=5 remote=ether://[01:00:5e:00:17:aa] local=dev://en0 counters={in={0i 0d} out={0i 0d}}
     faceid=6 remote=ether://[01:00:5e:00:17:aa] local=dev://en1 counters={in={0i 0d} out={0i 0d}}
   
   [cawka@cawka-mac NFD (master)]$ nfdc register /localhop 2
   Successful in name registration: ControlParameters(Name: /localhop, FaceId: 2, Origin: 0, Cost: 0, Flags: 1, ExpirationPeriod: 3600000 milliseconds, )
   

2. Try to fetch some data from the registered prefix

   [cawka@cawka-mac NFD (master)]$ ndn-tlv-peek /localhop/test
   

Expected: no data fetched and no changes in face list

Actual: no data fetched, but UDP4 multicast face disappears:

[cawka@cawka-mac NFD (master)]$ nfd-status -f
Faces:
  faceid=1 remote=internal:// local=internal:// counters={in={0i 35d} out={26i 0d}}
  faceid=3 remote=udp4://224.0.23.170:56363 local=udp4://127.0.0.1:56363 counters={in={0i 0d} out={0i 0d}}
  faceid=4 remote=ether://[01:00:5e:00:17:aa] local=dev://bridge0 counters={in={0i 0d} out={0i 0d}}
  faceid=5 remote=ether://[01:00:5e:00:17:aa] local=dev://en0 counters={in={0i 0d} out={0i 0d}}
  faceid=6 remote=ether://[01:00:5e:00:17:aa] local=dev://en1 counters={in={0i 0d} out={0i 0d}}

The following is in NFD's log:

1402873627.437623 INFO: [FaceTable] Removed face id=2 remote=udp4://224.0.23.170:56363 local=udp4://10.0.0.2:56363