1.\" $NetBSD: pad.4,v 1.10 2021/02/06 12:13:44 nia Exp $ 2.\" 3.\" Copyright (c) 2007 Jared D. McNeill <jmcneill@invisible.ca> 4.\" All rights reserved. 5.\" 6.\" Redistribution and use in source and binary forms, with or without 7.\" modification, are permitted provided that the following conditions 8.\" are met: 9.\" 1. Redistributions of source code must retain the above copyright 10.\" notice, this list of conditions and the following disclaimer. 11.\" 2. Redistributions in binary form must reproduce the above copyright 12.\" notice, this list of conditions and the following disclaimer in the 13.\" documentation and/or other materials provided with the distribution. 14.\" 15.\" THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 16.\" ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 17.\" TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 18.\" PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 19.\" BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 20.\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 21.\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 22.\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 23.\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 24.\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 25.\" POSSIBILITY OF SUCH DAMAGE. 26.\" 27.Dd February 6, 2021 28.Dt PAD 4 29.Os 30.Sh NAME 31.Nm pad 32.Nd Pseudo audio device driver 33.Sh SYNOPSIS 34.Cd "pseudo-device pad" 35.Cd "audio* at audiobus?" 36.Sh DESCRIPTION 37.Nm 38is a pseudo-device driver which provides support for feeding back PCM data 39from consumers of an 40.Xr audio 4 41device to userland. 42.Pp 43The raw PCM data readable from 44.Pa /dev/padN 45is encoded in stereo little-endian 16-bit linear PCM at 44100 Hz. 46.Sh FILES 47The 48.Nm 49pseudo-device driver receives data from 50.Pa /dev/audioN 51and feeds the raw PCM output to 52.Pa /dev/padN . 53.Pa /dev/audioN 54is created once 55.Pa /dev/padN 56is opened. 57.Bl -item 58.It 59.Pa /dev/audioN 60.It 61.Pa /dev/padN 62.El 63.Sh EXAMPLES 64The following example streams an MP3 to an Apple AirTunes compatible device: 65.Bd -literal -offset indent 66$ rtunes - < /dev/pad0 & 67$ mpg123 -a /dev/audio1 mozart.mp3 68.Ed 69.Pp 70Record the output of an application (in this case, audioplay): 71.Bd -literal -offset indent 72$ ffmpeg -f s16le -ar 44100 -ac 2 -i /dev/pad0 output.wav 73$ audioplay -d /dev/audio1 input.wav 74.Ed 75.Sh SEE ALSO 76.Xr audio 4 77.Sh HISTORY 78The 79.Nm 80driver 81appeared in 82.Nx 5.0 . 83.Sh AUTHORS 84.An Jared D. McNeill Aq Mt jmcneill@invisible.ca 85