NFD

I assume this is not the expected behavior, but please let me know if I'm missing anything here:

Summary:

• nfdc create tcp4 face ==> new face #x.
• nfdc create the same face ==> nfd-status presents multiple lines for the same uri, both attached to the same face #y != #x
• nfdc destroy #y ==> nfd-status still presents the uri, but attach it to an invalid face #.

Sample run:

$ build/bin/nfdc create tcp4://192.168.1.2
Face creation succeeded: ControlParameters(FaceId: 8, Uri: tcp4://192.168.1.2, )

$ build/bin/nfd-status 

(partial output): 
faceid=8 uri=tcp4://192.168.1.2:6363 counters={in={0i 0d} out={0i 0d}}

$ build/bin/nfdc create tcp4://192.168.1.2
Face creation succeeded: ControlParameters(FaceId: 11, Uri: tcp4://192.168.1.2, )

$ build/bin/nfd-status 

(partial output): 
faceid=11 uri=tcp4://192.168.1.2:6363 counters={in={0i 0d} out={0i 0d}}
faceid=11 uri=tcp4://192.168.1.2:6363 counters={in={0i 0d} out={0i 0d}}

$ build/bin/nfdc destroy 11

Face destroy succeeded: ControlParameters(FaceId: 11, )

$ build/bin/nfd-status (partial output): 

faceid=18446744073709551615 uri=tcp4://192.168.1.2:6363 counters={in={0i 0d} out={0i 0d}}