Comment 4 for bug 1211521

OK, the command is looking for a net subdirectory in the given /sys/ path, under that it'd find the interface name(s). So the old path works:

/devices/pci0000:00/0000:00:19.0 <- we have net under here

but the new one fails:

/devices/pci0000:00/0000:00:19.0/net/eth2 <- we are already in net/whatever, so looking for $path/net fails (finds nothing).