bug#2930: 23.0.92; `accept-process-output' and `sleep-for' do not run sentinels

>    (let ((p (start-process "bc" nil "bc"))
>          my-finished)
>      (set-process-sentinel p 'my-sentinel)
>      (process-send-string p "quit\n")
>      (while (not my-finished)
>        (accept-process-output nil 0.1)))

What happens of you pass `p' to accept-process-output, as would
seem natural?


        Stefan