>... What I'm suggesting is that streams gives the system the ability
>to better buffer events ...

Not in the sense that would help or hurt zs fifo overruns.  The
bottom-level code for dealing directly with the chip will always
be ugly.  A good streams design would help out with the rest of
the driver, though, especially the zs<-->keyboard, zs<-->mouse,
and zs?<-->?console hookups.  (This last in particular is virtually
unworkable in the current system -- the console can, in theory, be
split into `screen output' and `ttya input' or some such, but the
existing kernel is not really ready for that.)  What I did (bizarre
little `internal' open and close routines) was just a make-it-run
hack.

Chris