Run the UDP client using the dg_cli
function that broadcasts (Figure 20.5). How many
replies do you receive? Are the replies always in the same order?
Do the hosts on your network have synchronized clocks?
Put some printfs in Figure 20.10
after select returns to see whether it returns an error or
readability for one of the two descriptors. When the alarm
expires, does your system return EINTR or readability on
the pipe?
20.3
Run a tool such as tcpdump, if
available, and look for broadcast packets on your LAN; tcpdump
ether broadcast is the tcpdump command. To which
protocol suites do the broadcasts belong?
