implement sendto()/recvfrom() equivalents.

elsewhere as well.

request(), seek() or deliver_xxx() in order to start the data flow.
Autonomous generators must be genuinely autonomous (having their own
process), or otherwise arrange to be called.  TCP does this by
starting the retry timer immediately.

Add some debugging statements.

Add reference-counting to processes.

Add timer_running() test.

Achieved via Perl using:

perl -pi -e 's/pk_buff/io_buffer/g; s/Packet buffer/I\/O buffer/ig; ' \
	-e 's/pkbuff\.h/iobuf.h/g; s/pkb_/iob_/g; s/_pkb/_iob/g; ' \
	-e 's/pkb/iobuf/g; s/PKB/IOB/g;'

equivalents for alloc_pkb() and free_pkb(), which will be retired in
due course).

from the normal POSIX-style open()

ensure that we only drop our self-reference exactly once.

To maintain the guarantee that an object won't go out of scope
unexpectedly while one of its event handlers is being called, the
event-calling functions now automatically obtain and drop extra
references.

functions.

Add "xfer" to all xfer functions and "job" to all job functions.

the most generally useful way.

in code defining reference-counted objects.

Dehyphenate "data-transfer".

functions.

output buffering defintions and the like)

ISA 3c509 is currently non-functional, although the EISA (3c509-eisa) and
MCA (3c529) variants should build OK.

None of this code is yet tested.