Mercurial > sdl-ios-xcode
annotate docs/html/general.html @ 765:4c2ba6161939
Editors Note: The original patch was modified to use SDL_Delay() instead of
nanosleep because nanosleep may not be portable to all systems
using SDL with the ALSA backend. This may be a moot point with
the switch to blocking writes anyway...
Date: Sat, 27 Dec 2003 21:47:36 +0100
From: Michel Daenzer
To: Debian Bug Tracking System
Subject: [SDL] Bug#225252: [PATCH] ALSA fixes
Package: libsdl1.2debian-all
Version: 1.2.6-2
Severity: normal
Tags: patch
For SDL 1.2.6, the ALSA backend was changed to call snd_pcm_open() with
SND_PCM_NONBLOCK. That's a good idea per se, however, it causes high CPU
usage, interrupted sound and stuttering in some games here. Taking a nanosleep
whenever snd_pcm_writei() returns -EAGAIN fixes this, but I think it's more
efficient to use blocking mode for the actual sound playback. Feedback from the
SDL and ALSA lists appreciated.
The patch also fixes the default ALSA device to be used.
author | Sam Lantinga <slouken@libsdl.org> |
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date | Sun, 04 Jan 2004 15:40:50 +0000 |
parents | e5bc29de3f0a |
children | 355632dca928 |
rev | line source |
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0 | 1 <HTML |
2 ><HEAD | |
3 ><TITLE | |
4 >General</TITLE | |
5 ><META | |
6 NAME="GENERATOR" | |
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7 CONTENT="Modular DocBook HTML Stylesheet Version 1.64 |
0 | 8 "><LINK |
9 REL="HOME" | |
10 TITLE="SDL Library Documentation" | |
11 HREF="index.html"><LINK | |
12 REL="UP" | |
13 TITLE="SDL Reference" | |
14 HREF="reference.html"><LINK | |
15 REL="PREVIOUS" | |
16 TITLE="SDL Reference" | |
17 HREF="reference.html"><LINK | |
18 REL="NEXT" | |
19 TITLE="SDL_Init" | |
20 HREF="sdlinit.html"><META | |
21 NAME="KEYWORD" | |
22 CONTENT="general"><META | |
23 NAME="KEYWORD" | |
24 CONTENT="function"></HEAD | |
25 ><BODY | |
26 CLASS="CHAPTER" | |
27 BGCOLOR="#FFF8DC" | |
28 TEXT="#000000" | |
29 LINK="#0000ee" | |
30 VLINK="#551a8b" | |
31 ALINK="#ff0000" | |
32 ><DIV | |
33 CLASS="NAVHEADER" | |
34 ><TABLE | |
35 WIDTH="100%" | |
36 BORDER="0" | |
37 CELLPADDING="0" | |
38 CELLSPACING="0" | |
39 ><TR | |
40 ><TH | |
41 COLSPAN="3" | |
42 ALIGN="center" | |
43 >SDL Library Documentation</TH | |
44 ></TR | |
45 ><TR | |
46 ><TD | |
47 WIDTH="10%" | |
48 ALIGN="left" | |
49 VALIGN="bottom" | |
50 ><A | |
51 HREF="reference.html" | |
52 >Prev</A | |
53 ></TD | |
54 ><TD | |
55 WIDTH="80%" | |
56 ALIGN="center" | |
57 VALIGN="bottom" | |
58 ></TD | |
59 ><TD | |
60 WIDTH="10%" | |
61 ALIGN="right" | |
62 VALIGN="bottom" | |
63 ><A | |
64 HREF="sdlinit.html" | |
65 >Next</A | |
66 ></TD | |
67 ></TR | |
68 ></TABLE | |
69 ><HR | |
70 ALIGN="LEFT" | |
71 WIDTH="100%"></DIV | |
72 ><DIV | |
73 CLASS="CHAPTER" | |
74 ><H1 | |
75 ><A | |
76 NAME="GENERAL" | |
77 >Chapter 5. General</A | |
78 ></H1 | |
79 ><DIV | |
80 CLASS="TOC" | |
81 ><DL | |
82 ><DT | |
83 ><B | |
84 >Table of Contents</B | |
85 ></DT | |
86 ><DT | |
87 ><A | |
88 HREF="sdlinit.html" | |
89 >SDL_Init</A | |
90 > — Initializes SDL</DT | |
91 ><DT | |
92 ><A | |
93 HREF="sdlinitsubsystem.html" | |
94 >SDL_InitSubSystem</A | |
95 > — Initialize subsystems</DT | |
96 ><DT | |
97 ><A | |
98 HREF="sdlquitsubsystem.html" | |
99 >SDL_QuitSubSystem</A | |
100 > — Shut down a subsystem</DT | |
101 ><DT | |
102 ><A | |
103 HREF="sdlquit.html" | |
104 >SDL_Quit</A | |
105 > — Shut down SDL</DT | |
106 ><DT | |
107 ><A | |
108 HREF="sdlwasinit.html" | |
109 >SDL_WasInit</A | |
110 > — Check which subsystems are initialized</DT | |
181
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111 ><DT |
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112 ><A |
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113 HREF="sdlgeterror.html" |
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114 >SDL_GetError</A |
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115 > — Get SDL error string</DT |
0 | 116 ></DL |
117 ></DIV | |
118 ><P | |
119 >Before SDL can be used in a program it must be initialized with <A | |
120 HREF="sdlinit.html" | |
121 ><TT | |
122 CLASS="FUNCTION" | |
123 >SDL_Init</TT | |
124 ></A | |
125 >. <TT | |
126 CLASS="FUNCTION" | |
127 >SDL_Init</TT | |
128 > initializes all the subsystems that the user requests (video, audio, joystick, timers and/or cdrom). Once SDL is initialized with <TT | |
129 CLASS="FUNCTION" | |
130 >SDL_Init</TT | |
131 > subsystems can be shut down and initialized as needed using <A | |
132 HREF="sdlinitsubsystem.html" | |
133 ><TT | |
134 CLASS="FUNCTION" | |
135 >SDL_InitSubSystem</TT | |
136 ></A | |
137 > and <A | |
138 HREF="sdlquitsubsystem.html" | |
139 ><TT | |
140 CLASS="FUNCTION" | |
141 >SDL_QuitSubSystem</TT | |
142 ></A | |
143 >.</P | |
144 ><P | |
145 >SDL must also be shut down before the program exits to make sure it cleans up correctly. Calling <A | |
146 HREF="sdlquit.html" | |
147 ><TT | |
148 CLASS="FUNCTION" | |
149 >SDL_Quit</TT | |
150 ></A | |
151 > shuts down all subsystems and frees any resources allocated to SDL.</P | |
152 ></DIV | |
153 ><DIV | |
154 CLASS="NAVFOOTER" | |
155 ><HR | |
156 ALIGN="LEFT" | |
157 WIDTH="100%"><TABLE | |
158 WIDTH="100%" | |
159 BORDER="0" | |
160 CELLPADDING="0" | |
161 CELLSPACING="0" | |
162 ><TR | |
163 ><TD | |
164 WIDTH="33%" | |
165 ALIGN="left" | |
166 VALIGN="top" | |
167 ><A | |
168 HREF="reference.html" | |
169 >Prev</A | |
170 ></TD | |
171 ><TD | |
172 WIDTH="34%" | |
173 ALIGN="center" | |
174 VALIGN="top" | |
175 ><A | |
176 HREF="index.html" | |
177 >Home</A | |
178 ></TD | |
179 ><TD | |
180 WIDTH="33%" | |
181 ALIGN="right" | |
182 VALIGN="top" | |
183 ><A | |
184 HREF="sdlinit.html" | |
185 >Next</A | |
186 ></TD | |
187 ></TR | |
188 ><TR | |
189 ><TD | |
190 WIDTH="33%" | |
191 ALIGN="left" | |
192 VALIGN="top" | |
193 >SDL Reference</TD | |
194 ><TD | |
195 WIDTH="34%" | |
196 ALIGN="center" | |
197 VALIGN="top" | |
198 ><A | |
199 HREF="reference.html" | |
200 >Up</A | |
201 ></TD | |
202 ><TD | |
203 WIDTH="33%" | |
204 ALIGN="right" | |
205 VALIGN="top" | |
206 >SDL_Init</TD | |
207 ></TR | |
208 ></TABLE | |
209 ></DIV | |
210 ></BODY | |
211 ></HTML | |
212 > |