- The receiver now sends keep-alive messages to the generator
when it is actively doing work and hasn't sent anything
recently. This ensures that the generator won't timeout
if the receiver is working hard.
- The perform_io() code has improved keep-alive participation.
- Allow the sender to send some keep-alive messages, which
ensures that if it is in a lull, it can probe the socket.
The receiving side also switches timeout handling from the receiver to
the generator, which obviates the need for the sender to send any
keep-alive messages at all (for protocol 31 and beyond). Given this
setup, all keep-alive messages are now sent as empty MSG_DATA messages,
with MSG_NOOP messages only being understood and (when necessary) acted
upon to forward a keep-alive event to an older receiver. This is both
safer and more compatible with older versions.
- The receiver notifies the generator if it is exiting with an error,
and then, if it is a server, waits around for the generator to die.
This ensures that the client side has time to read the error.
- The generator or sender will notifiy the other side of the transfer of
an error-exit value if protocol 31 is in effect. This will get rid of
some "connection unexpectedly closed" errors that are really expected
events due to a fatal exit on the other side.
Files-from data is now sent as multiplexed I/O so that it can mingle
with any messages (such as debug output). Requires protocol 31.
Protocol 31 no longer disables output verbosity in a couple instances
that used to cause protocol issues.
Got rid of MSG_* messages that have implied raw data that follows after
them. We instead send a negative index value as a part of the raw data
stream, which is guaranteed to be output together with the following
data. This only affects the (in-progress) protocol 31 and the (self-
contained) communication stream from the receiver to the generator.
Added --debug=IO and improved --debug=FLIST. Some --debug=IO output
requires --msgs2stderr to be used to see it (i.e. sending a message
about sending a message would send another message, ad infinitum).
