Errata

The text says "Keep in mind that terminate_child/2, restart_child/2, and delete_child/2 cannot be used with simple_one_for_one strategies:" but this is not completely correct. The terminate_child/2 function can be used with simple_one_for_one as long as the child process pid, not the child specification identifier, is passed for the second argument. This is clearly documented under http://erlang.org/doc/man/supervisor.html#terminate_child-2 : "If the supervisor is simple_one_for_one, Id must be the pid() of the child process."

the record definition 'hostent' is missing commas between the fields

Note from the Author or Editor:
Should be

-record(hostent,
{
h_name, % offical name of host
h_aliases = [], % alias list
h_addrtype, % host address type
h_length, % length of address
h_addr_list = [] % list of addresses from name server
}).

stop() calls gen_fsm:sync_send_all_state_event, but we implement handle_event (not handle_sync_event). Maybe stop() should call gen_fsm:send_all_state_event instead?

Note from the Author or Editor:
This is already fixed in copyedit. The fix is, near the bottom of page 137, to change "the event is handled in handle_event/3" to "the event is handled in
handle_sync_event/4" and change "handle_event(stop, _State, LoopData)" to "handle_sync_event(stop, _From, _State, LoopData)".

In the sentence

Any other events coming out of sequence (such as Sunset when in state Day) are handled only after a transition to a state where they can be dealt with.

the phrase in parentheses should be either "(such as Sunrise when in state Day)" OR "such as Sunset when in state Night)"

Note from the Author or Editor:
Already fixed in copyedit. Changed "In state Night, event Sunset causes" to "In state Night, event Sunrise causes" and also changed "(such as Sunset when in state Day)" to "(such as Sunrise when in state Day)".

`terminate/3` function at the top of page 154 doesn't contain any code to display:
Display:Shutting Down
which is in the sample run.

Note from the Author or Editor:
Fixed, there was a discrepancy with the code.