eventually get updated.

provides them.

permanent processes, rather than requiring each one to have its own
initialisation function.

attempt at triggering TCP-related protocols to start).

structures.

DHCP still broken and #if 0'd out.

current working URI.

implement sendto()/recvfrom() equivalents.

allows us to avoid execution loops without having to hack around the
image registration order.

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.

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

from the normal POSIX-style open()