All of lore.kernel.org
 help / color / mirror / Atom feed
From: Clemens Ladisch <clemens@ladisch.de>
To: Colin Guthrie <gmane@colin.guthr.ie>
Cc: Arun Raghavan <arun.raghavan@collabora.co.uk>,
	ALSA Development Mailing List <alsa-devel@alsa-project.org>
Subject: Re: Event flood on USB disconnect
Date: Mon, 03 Oct 2011 23:50:41 +0200	[thread overview]
Message-ID: <4E8A2E31.2080002@ladisch.de> (raw)
In-Reply-To: <4E89741B.3050602@colin.guthr.ie>

Colin Guthrie wrote:
> Would a POLLERR|POLLNVAL be received any time
> when normal operations will continue afterwards? e.g. should we use this
> error as an indicator to ignore it forever or, e.g., just for a finite
> period of time like 1s.

POLLERR means that the PCM device is in a state where it cannot transfer
data.  This typically happens on an xrun or when the device is unplugged,
if the first system call after that event is poll() and not write().
The error handling should be the same (snd_pcm_prepare(), which might
fail).

A disconnected device returns POLLERR|POLLNVAL, while any other error
state returns POLLOUT|POLLERR.


Regards,
Clemens

      reply	other threads:[~2011-10-03 21:51 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-10-01  8:49 Event flood on USB disconnect Arun Raghavan
2011-10-01  8:53 ` Arun Raghavan
2011-10-04  2:30   ` Raymond Yau
2011-10-04  3:10     ` Arun Raghavan
2011-10-03  8:36 ` Colin Guthrie
2011-10-03 21:50   ` Clemens Ladisch [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=4E8A2E31.2080002@ladisch.de \
    --to=clemens@ladisch.de \
    --cc=alsa-devel@alsa-project.org \
    --cc=arun.raghavan@collabora.co.uk \
    --cc=gmane@colin.guthr.ie \
    /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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.