From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stefan Schoenleitner Subject: io-plugin does not call start callback function Date: Thu, 03 Dec 2009 12:49:32 +0100 Message-ID: <4B17A5CC.5050906@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from netfinity.tbmn.org (mail.tbmn.org [88.117.197.126]) by alsa0.perex.cz (Postfix) with ESMTP id 4FEF0243FC for ; Thu, 3 Dec 2009 12:49:34 +0100 (CET) Received: from localhost (localhost.localdomain [127.0.0.1]) by netfinity.tbmn.org (Postfix) with ESMTP id 096EF4BEE0 for ; Thu, 3 Dec 2009 12:49:34 +0100 (CET) Received: from netfinity.tbmn.org ([127.0.0.1]) by localhost (netfinity.tbmn.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id qM119CroWCnp for ; Thu, 3 Dec 2009 12:49:33 +0100 (CET) Received: from [192.168.1.5] (chello080108001212.35.11.tuwien.teleweb.at [80.108.1.212]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) (Authenticated sender: mne@tbmn.org) by netfinity.tbmn.org (Postfix) with ESMTPSA id A2BE94BE05 for ; Thu, 3 Dec 2009 12:49:33 +0100 (CET) List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: alsa-devel-bounces@alsa-project.org Errors-To: alsa-devel-bounces@alsa-project.org To: "alsa-devel@alsa-project.org" List-Id: alsa-devel@alsa-project.org Hi, I'm writing an io plugin that should transfer all PCM samples to a UNIX socket. For this reason in my plugin I open the socket and then fill the plugin struct like this: socketdump->io.mmap_rw = 0; socketdump->io.poll_fd = socketdump->sock_fd; socketdump->io.poll_events = POLLOUT; Thus for my understanding (the alsa doc is really bad), every time the socket file descriptor is available for writing the alsa plugin would generally speaking issue a data transfer. However, when playing audio over that plugin for some reason the start callback function is never called. Instead I get output like this: socketdump_hw_constraint:417 26944 _snd_pcm_socketdump_open:585 26944 SND_PCM_PLUGIN_DEFINE_FUNC(): done, err=0 Playing WAVE 'test_8khz_16LE_mono.wav' : Signed 16 bit Little Endian, Rate 8000 Hz, Mono snd_pcm_socketdump_prepare:309 26944 Preparing with io->period_size=164 io->buffer_size=3936 snd_pcm_socketdump_pointer:229 26944 hw_ptr: 0 () snd_pcm_socketdump_write:268 26944 snd_pcm_socketdump_write(): areas->step=16 areas->first=0 areas->addr=0x22f1f60 offset=0, size=164 io->nonblock=0 ...... Do you have any idea why the start callback function is not called at all ? cheers, stefan