From mboxrd@z Thu Jan  1 00:00:00 1970
From: erik quanstrom <quanstro@quanstro.net>
Date: Tue, 31 Dec 2013 14:50:27 -0500
To: 9fans@9fans.net
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Subject: Re: [9fans] "gpio device" for Plan 9
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On Tue Dec 31 14:40:29 EST 2013, edgecomberts@gmail.com wrote:

> Erik,
>
> Just for the purposes of edification (and curiosity), are you able to
> elaborate on "long reads"? Its understandable such a scheme would be
> implemented in the network drivers, but how exactly does it work, as
> opposed to a polling scheme or an ISR? I will, of course, Google in a sec
> as well.

it could be that i misunderstood the op's point.  what i understood from the
original post was a scheme was envisioned where a user process would poll a
status file to get interrupt status.  if i understood this correctly, then providing
an interrupt file that returns even 0 bytes when there's an interrupt would be
an alternative providing interrupt semantics to the up.  there are some
bits to work out if the user process falls behind, but it's no different than a
network device.

does that answer your question?

- erik