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Deleted a call to X__PumpEvents at the end of X11_GL_InitExtensions(). This function is being called from SDL_RecreateWindow at a point when the numwindows value in is incorrect. The result is that an illegal access is being made in X_PumpEvents when it tries to look up the windows ID of the source of an event. Taking out that call does not seem to have any effect on the testgl. But, I would be happy if someone else took a look at this problem and found a fix higher up the stack.
author Bob Pendleton <bob@pendleton.com>
date Sat, 01 Mar 2008 20:34:36 +0000
parents 355632dca928
children
line wrap: on
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<HTML
><HEAD
><TITLE
>Initializing SDL</TITLE
><META
NAME="GENERATOR"
CONTENT="Modular DocBook HTML Stylesheet Version 1.76b+
"><LINK
REL="HOME"
TITLE="SDL Library Documentation"
HREF="index.html"><LINK
REL="UP"
TITLE="The Basics"
HREF="guidethebasics.html"><LINK
REL="PREVIOUS"
TITLE="The Basics"
HREF="guidethebasics.html"><LINK
REL="NEXT"
TITLE="Graphics and Video"
HREF="guidevideo.html"></HEAD
><BODY
CLASS="SECT1"
BGCOLOR="#FFF8DC"
TEXT="#000000"
LINK="#0000ee"
VLINK="#551a8b"
ALINK="#ff0000"
><DIV
CLASS="NAVHEADER"
><TABLE
SUMMARY="Header navigation table"
WIDTH="100%"
BORDER="0"
CELLPADDING="0"
CELLSPACING="0"
><TR
><TH
COLSPAN="3"
ALIGN="center"
>SDL Library Documentation</TH
></TR
><TR
><TD
WIDTH="10%"
ALIGN="left"
VALIGN="bottom"
><A
HREF="guidethebasics.html"
ACCESSKEY="P"
>Prev</A
></TD
><TD
WIDTH="80%"
ALIGN="center"
VALIGN="bottom"
>Chapter 1. The Basics</TD
><TD
WIDTH="10%"
ALIGN="right"
VALIGN="bottom"
><A
HREF="guidevideo.html"
ACCESSKEY="N"
>Next</A
></TD
></TR
></TABLE
><HR
ALIGN="LEFT"
WIDTH="100%"></DIV
><DIV
CLASS="SECT1"
><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
></DIV
></DIV
><DIV
CLASS="NAVFOOTER"
><HR
ALIGN="LEFT"
WIDTH="100%"><TABLE
SUMMARY="Footer navigation table"
WIDTH="100%"
BORDER="0"
CELLPADDING="0"
CELLSPACING="0"
><TR
><TD
WIDTH="33%"
ALIGN="left"
VALIGN="top"
><A
HREF="guidethebasics.html"
ACCESSKEY="P"
>Prev</A
></TD
><TD
WIDTH="34%"
ALIGN="center"
VALIGN="top"
><A
HREF="index.html"
ACCESSKEY="H"
>Home</A
></TD
><TD
WIDTH="33%"
ALIGN="right"
VALIGN="top"
><A
HREF="guidevideo.html"
ACCESSKEY="N"
>Next</A
></TD
></TR
><TR
><TD
WIDTH="33%"
ALIGN="left"
VALIGN="top"
>The Basics</TD
><TD
WIDTH="34%"
ALIGN="center"
VALIGN="top"
><A
HREF="guidethebasics.html"
ACCESSKEY="U"
>Up</A
></TD
><TD
WIDTH="33%"
ALIGN="right"
VALIGN="top"
>Graphics and Video</TD
></TR
></TABLE
></DIV
></BODY
></HTML
>