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Commercial-OSS-on-Solaris patch... --ryan. Date: Sun, 14 Aug 2005 23:06:40 -0500 From: Shawn Walker <binarycrusader@gmail.com> To: sdl@libsdl.org Subject: [SDL] [PATCH] Audio Detection Bug When using the OSS commercial drivers under Solaris 10, SDL will not properly initialise OSS audio support (dsp) if /dev/sound exists. Under Solaris (as far as I understand) /dev/sound is provided as a means of accessing a BSD style audio device, not the OSS device. SDL assumes that if /dev/sound exists, then it must be running on a Linux 2.4 system and should make the dsp device path /dev/sound/dsp. This is wrong. When using the OSS commercial drivers under Solaris, the dsp device is always referenced as /dev/dsp normally. My proposed fix is to stat the dsp device in /dev/sound to make sure it exists, before assuming /dev/sound/dsp as the audio device: http://icculus.org/~eviltypeguy/SDL_audiodev.patch I'm sure there may be a better way to do it, but the above patch is what worked for me. --=20 Shawn Walker, Software and Systems Analyst binarycrusader@gmail.com - http://binarycrusader.blogspot.com/
author Ryan C. Gordon <icculus@icculus.org>
date Thu, 08 Sep 2005 07:15:44 +0000
parents 355632dca928
children
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<HTML
><HEAD
><TITLE
>Audio</TITLE
><META
NAME="GENERATOR"
CONTENT="Modular DocBook HTML Stylesheet Version 1.76b+
"><LINK
REL="HOME"
TITLE="SDL Library Documentation"
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HREF="sdlaudiospec.html"><META
NAME="KEYWORD"
CONTENT="audio"><META
NAME="KEYWORD"
CONTENT="function"></HEAD
><BODY
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><DIV
CLASS="CHAPTER"
><H1
><A
NAME="AUDIO"
></A
>Chapter 10. Audio</H1
><DIV
CLASS="TOC"
><DL
><DT
><B
>Table of Contents</B
></DT
><DT
><A
HREF="sdlaudiospec.html"
>SDL_AudioSpec</A
>&nbsp;--&nbsp;Audio Specification Structure</DT
><DT
><A
HREF="sdlopenaudio.html"
>SDL_OpenAudio</A
>&nbsp;--&nbsp;Opens the audio device with the desired parameters.</DT
><DT
><A
HREF="sdlpauseaudio.html"
>SDL_PauseAudio</A
>&nbsp;--&nbsp;Pauses and unpauses the audio callback processing</DT
><DT
><A
HREF="sdlgetaudiostatus.html"
>SDL_GetAudioStatus</A
>&nbsp;--&nbsp;Get the current audio state</DT
><DT
><A
HREF="sdlloadwav.html"
>SDL_LoadWAV</A
>&nbsp;--&nbsp;Load a WAVE file</DT
><DT
><A
HREF="sdlfreewav.html"
>SDL_FreeWAV</A
>&nbsp;--&nbsp;Frees previously opened WAV data</DT
><DT
><A
HREF="sdlaudiocvt.html"
>SDL_AudioCVT</A
>&nbsp;--&nbsp;Audio Conversion Structure</DT
><DT
><A
HREF="sdlbuildaudiocvt.html"
>SDL_BuildAudioCVT</A
>&nbsp;--&nbsp;Initializes a SDL_AudioCVT structure for conversion</DT
><DT
><A
HREF="sdlconvertaudio.html"
>SDL_ConvertAudio</A
>&nbsp;--&nbsp;Convert audio data to a desired audio format.</DT
><DT
><A
HREF="sdlmixaudio.html"
>SDL_MixAudio</A
>&nbsp;--&nbsp;Mix audio data</DT
><DT
><A
HREF="sdllockaudio.html"
>SDL_LockAudio</A
>&nbsp;--&nbsp;Lock out the callback function</DT
><DT
><A
HREF="sdlunlockaudio.html"
>SDL_UnlockAudio</A
>&nbsp;--&nbsp;Unlock the callback function</DT
><DT
><A
HREF="sdlcloseaudio.html"
>SDL_CloseAudio</A
>&nbsp;--&nbsp;Shuts down audio processing and closes the audio device.</DT
></DL
></DIV
><P
>Sound on the computer is translated from waves that you hear into a series of 
values, or samples, each representing the amplitude of the wave.  When these
samples are sent in a stream to a sound card, an approximation of the original
wave can be recreated.  The more bits used to represent the amplitude, and the
greater frequency these samples are gathered, the closer the approximated
sound is to the original, and the better the quality of sound.</P
><P
>This library supports both 8 and 16 bit signed and unsigned sound samples,
at frequencies ranging from 11025 Hz to 44100 Hz, depending on the 
underlying hardware.  If the hardware doesn't support the desired audio
format or frequency, it can be emulated if desired (See 
<A
HREF="sdlopenaudio.html"
><TT
CLASS="FUNCTION"
>SDL_OpenAudio()</TT
></A
>)</P
><P
>A commonly supported audio format is 16 bits per sample at 22050 Hz.</P
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