view docs/html/sdlwasinit.html @ 4355:9b464226e541 SDL-1.2

Fixed bug #855 Ludwig Nussel 2009-10-18 06:31:52 PDT an mprotect call was added to fix bug 528. However that results in a buffer that allows writing and code execution. Ie the no-execute security features of modern operating systems are defeated this way. Two mprotect calls are needed. One to make the buffer executable but not writeable when done and another one to make the buffer writeable again if the content needs to be changed.
author Sam Lantinga <slouken@libsdl.org>
date Sun, 18 Oct 2009 17:31:37 +0000
parents 355632dca928
children
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><H1
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>SDL_WasInit</H1
><DIV
CLASS="REFNAMEDIV"
><A
NAME="AEN617"
></A
><H2
>Name</H2
>SDL_WasInit&nbsp;--&nbsp;Check which subsystems are initialized</DIV
><DIV
CLASS="REFSYNOPSISDIV"
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NAME="AEN620"
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><H2
>Synopsis</H2
><DIV
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><P
></P
><PRE
CLASS="FUNCSYNOPSISINFO"
>#include "SDL.h"</PRE
><P
><CODE
><CODE
CLASS="FUNCDEF"
>Uint32 <B
CLASS="FSFUNC"
>SDL_WasInit</B
></CODE
>(Uint32 flags);</CODE
></P
><P
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><DIV
CLASS="REFSECT1"
><A
NAME="AEN627"
></A
><H2
>Description</H2
><P
><TT
CLASS="FUNCTION"
>SDL_WasInit</TT
> allows you to see which SDL subsytems have been <A
HREF="sdlinit.html"
>initialized</A
>. <TT
CLASS="PARAMETER"
><I
>flags</I
></TT
> is a bitwise OR'd combination of the subsystems you wish to check (see <A
HREF="sdlinit.html"
><TT
CLASS="FUNCTION"
>SDL_Init</TT
></A
> for a list of subsystem flags).</P
></DIV
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><A
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></A
><H2
>Return Value</H2
><P
><TT
CLASS="FUNCTION"
>SDL_WasInit</TT
> returns a bitwised OR'd combination of the initialized subsystems.</P
></DIV
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><A
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></A
><H2
>Examples</H2
><PRE
CLASS="PROGRAMLISTING"
>&#13;/* Here are several ways you can use SDL_WasInit() */

/* Get init data on all the subsystems */
Uint32 subsystem_init;

subsystem_init=SDL_WasInit(SDL_INIT_EVERYTHING);

if(subsystem_init&#38;SDL_INIT_VIDEO)
  printf("Video is initialized.\n");
else
  printf("Video is not initialized.\n");



/* Just check for one specfic subsystem */

if(SDL_WasInit(SDL_INIT_VIDEO)!=0)
  printf("Video is initialized.\n");
else
  printf("Video is not initialized.\n");




/* Check for two subsystems */

Uint32 subsystem_mask=SDL_INIT_VIDEO|SDL_INIT_AUDIO;

if(SDL_WasInit(subsystem_mask)==subsystem_mask)
  printf("Video and Audio initialized.\n");
else
  printf("Video and Audio not initialized.\n");&#13;</PRE
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><A
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><TT
CLASS="FUNCTION"
>SDL_Init</TT
></A
>,
<A
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>SDL_Subsystem</TT
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