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Date: Mon, 30 Aug 2004 18:20:25 +0200 From: Joost Baas Subject: why call arts artsc? I, and a few other people at the mplayer-docs-mailinglist were wondering why you decided to call arts artsc. I understand usually users have nothing to do with libsdl, just developers, but because you can choose the audio-driver being used by mplayer, one of which is sdl, and you can also choose the sdl subdriver, it is necessary to have a well-known or logical name. artsc is not the logical choice, and it's very hard to look up the right name if you don't know what you're looking for.
author Sam Lantinga <slouken@libsdl.org>
date Fri, 17 Sep 2004 13:25:06 +0000
parents 355632dca928
children
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<HTML
><HEAD
><TITLE
>Initializing SDL</TITLE
><META
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>Chapter 1. The Basics</TD
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><DIV
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><H1
CLASS="SECT1"
><A
NAME="GUIDEBASICSINIT"
></A
>Initializing SDL</H1
><P
>SDL is composed of eight subsystems - Audio, CDROM, Event Handling, File I/O, Joystick Handling, Threading, Timers and Video. Before you can use any of these subsystems they must be initialized by calling <A
HREF="sdlinit.html"
><TT
CLASS="FUNCTION"
>SDL_Init</TT
></A
> (or <A
HREF="sdlinitsubsystem.html"
><TT
CLASS="FUNCTION"
>SDL_InitSubSystem</TT
></A
>). <TT
CLASS="FUNCTION"
>SDL_Init</TT
> must be called before any other SDL function. It automatically initializes the Event Handling, File I/O and Threading subsystems and it takes a parameter specifying which other subsystems to initialize. So, to initialize the default subsystems and the Video subsystems you would call:
<PRE
CLASS="PROGRAMLISTING"
>    SDL_Init ( SDL_INIT_VIDEO );</PRE
>
To initialize the default subsystems, the Video subsystem and the Timers subsystem you would call:
<PRE
CLASS="PROGRAMLISTING"
>    SDL_Init ( SDL_INIT_VIDEO | SDL_INIT_TIMER );</PRE
></P
><P
><TT
CLASS="FUNCTION"
>SDL_Init</TT
> is complemented by <A
HREF="sdlquit.html"
><TT
CLASS="FUNCTION"
>SDL_Quit</TT
></A
> (and <A
HREF="sdlquitsubsystem.html"
><TT
CLASS="FUNCTION"
>SDL_QuitSubSystem</TT
></A
>). <TT
CLASS="FUNCTION"
>SDL_Quit</TT
> shuts down all subsystems, including the default ones. It should always be called before a SDL application exits.</P
><P
>With <TT
CLASS="FUNCTION"
>SDL_Init</TT
> and <TT
CLASS="FUNCTION"
>SDL_Quit</TT
> firmly embedded in your programmers toolkit you can write your first and most basic SDL application. However, we must be prepare to handle errors. Many SDL functions return a value and indicates whether the function has succeeded or failed, <TT
CLASS="FUNCTION"
>SDL_Init</TT
>, for instance, returns -1 if it could not initialize a subsystem. SDL provides a useful facility that allows you to determine exactly what the problem was, every time an error occurs within SDL an error message is stored which can be retrieved using <TT
CLASS="FUNCTION"
>SDL_GetError</TT
>. Use this often, you can never know too much about an error.</P
><DIV
CLASS="EXAMPLE"
><A
NAME="AEN60"
></A
><P
><B
>Example 1-1. Initializing SDL</B
></P
><PRE
CLASS="PROGRAMLISTING"
>#include "SDL.h"   /* All SDL App's need this */
#include &#60;stdio.h&#62;

int main(int argc, char *argv[]) {
    
    printf("Initializing SDL.\n");
    
    /* Initialize defaults, Video and Audio */
    if((SDL_Init(SDL_INIT_VIDEO|SDL_INIT_AUDIO)==-1)) { 
        printf("Could not initialize SDL: %s.\n", SDL_GetError());
        exit(-1);
    }

    printf("SDL initialized.\n");

    printf("Quiting SDL.\n");
    
    /* Shutdown all subsystems */
    SDL_Quit();
    
    printf("Quiting....\n");

    exit(0);
}&#13;</PRE
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