8bfcc5ad34
(i.e., 10baseT carrier/no carrier) of an interface from scripts ifconfig -s <interface> will exit with a false status if the interface reports its unconnected. -s also works in conjunction with -l and -a, filtering out interfaces which are reporting down. Also, add -b (which shows only broadcast interfaces with -l and -a). I find these options useful in network autoconfig scripts for mobile systems.