view docs/html/sdlgetkeystate.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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>SDL_GetKeyState</H1
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><H2
>Name</H2
>SDL_GetKeyState&nbsp;--&nbsp;Get a snapshot of the current keyboard state</DIV
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>Synopsis</H2
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><P
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><PRE
CLASS="FUNCSYNOPSISINFO"
>#include "SDL.h"</PRE
><P
><CODE
><CODE
CLASS="FUNCDEF"
>Uint8 *<B
CLASS="FSFUNC"
>SDL_GetKeyState</B
></CODE
>(int *numkeys);</CODE
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><H2
>Description</H2
><P
>Gets a snapshot of the current keyboard state. The current state is return as a pointer to an array, the size of this array is stored in <TT
CLASS="PARAMETER"
><I
>numkeys</I
></TT
>. The array is indexed by the <A
HREF="sdlkey.html"
><TT
CLASS="LITERAL"
>SDLK_*</TT
></A
> symbols. A value of 1 means the key is pressed and a value of 0 means its not. The pointer returned is a pointer to an internal SDL array and should not be freed by the caller.</P
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>Note: </B
>Use <A
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><TT
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>SDL_PumpEvents</TT
></A
> to update the state array.</P
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><H2
>Example</H2
><P
><PRE
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>Uint8 *keystate = SDL_GetKeyState(NULL);
if ( keystate[SDLK_RETURN] ) printf("Return Key Pressed.\n");</PRE
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><P
><A
HREF="sdlkey.html"
><TT
CLASS="LITERAL"
>SDL Key Symbols</TT
></A
>,
<A
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>SDL_PumpEvents</TT
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