We said that almost all fields in an IPv6 header
and all extension headers are available to the application through
socket options or ancillary data. What information in an IPv6
datagram is not available to an
application?
What happens in Figure 28.40 if for
some reason the client stops reading from its Unix domain
connection to the icmpd daemon and lots of ICMP errors
arrive for the client? What is the easiest solution?
If we specify the subnet-directed broadcast
address to our ping program, it works. That is, a
broadcast ICMP echo request is sent as a link-layer broadcast, even
though we do not set the SO_BROADCAST socket option.
Why?