framebuf event loop to take n i/o fd's as parameters and also allow
dynamic add/remove of fd's. (not tested except for one fd, but more
changes coming soon)
and event handling mechanisms required in file servers with blocking
I/O backends. puffs_framebuf is built on the concept of puffs_cc
and uses those to multiplex execution where needed.
File systems are required to implement three methods:
* read frame
* write frame
* compare if frame is a response to the given one
Memory management is provided by puffs_framebuf, but the file
systems must still, of course, interpret the protocol and do e.g.
byte order conversion.
As always, puffs_framebuf is work in progress. Current users are
mount_psshfs and mount_9p.
pooka