> When a program (acme in the above example) exits,
> the server fails on the assertion:
> 	assert failed: r == nr
> in lib9p.  I think I must make sure that 'Req *req'
> is valid before the child process calls respond().

See the discussion of flush in the man page.  After you
respond to a flush request you have to make sure that
r->oldreq will never get responded to.

Russ