9fans - fans of the OS Plan 9 from Bell Labs
 help / color / mirror / Atom feed
From: Gorka Guardiola <paurea@gmail.com>
To: Fans of the OS Plan 9 from Bell Labs <9fans@9fans.net>
Subject: Re: [9fans] usb/serial control open
Date: Sun, 23 Mar 2014 20:53:02 +0100	[thread overview]
Message-ID: <CACm3i_idXKDgVjPMbpZ2nMigh7wmazn6RVU40tWq1B80jLAVxg@mail.gmail.com> (raw)
In-Reply-To: <CACm3i_jSpTnzQWurOEOxWxPBGHMhcWMfRCGha2yOaaoyy0zcLw@mail.gmail.com>

> What do you return on read if you don´t know the state?
> For some devices if you don´t set the state, you have no idea.
> You can do it in read, but it seemed more intuitive in open at the
> time, (and you don´t
> set the state on every read).
>

What I meant, is if you
write then read, the read does not set the state.
if you read then write, it does.
It is cleaner to set it on open.

The rule is simple, the first open sets the state.
As I said, the "first" part is missing :-).

G.



      parent reply	other threads:[~2014-03-23 19:53 UTC|newest]

Thread overview: 15+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-03-23 18:09 erik quanstrom
2014-03-23 18:34 ` Gorka Guardiola
2014-03-23 18:55   ` erik quanstrom
2014-03-23 19:47     ` Gorka Guardiola
2014-03-23 19:55       ` Gorka Guardiola
2014-03-23 20:32         ` erik quanstrom
2014-03-23 21:08           ` Gorka Guardiola
2014-03-24  1:49             ` erik quanstrom
2014-03-23 21:32           ` Bakul Shah
2014-03-23 21:53             ` erik quanstrom
2014-03-23 22:02               ` Bakul Shah
2014-03-24  0:32                 ` erik quanstrom
2014-03-24  0:41                   ` Bakul Shah
2014-03-23  5:04                     ` lucio
2014-03-23 19:53   ` Gorka Guardiola [this message]

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=CACm3i_idXKDgVjPMbpZ2nMigh7wmazn6RVU40tWq1B80jLAVxg@mail.gmail.com \
    --to=paurea@gmail.com \
    --cc=9fans@9fans.net \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).