view docs/html/sdlpollevent.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_PollEvent</H1
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><H2
>Name</H2
>SDL_PollEvent&nbsp;--&nbsp;Polls for currently pending events.</DIV
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>Synopsis</H2
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><PRE
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>#include "SDL.h"</PRE
><P
><CODE
><CODE
CLASS="FUNCDEF"
>int <B
CLASS="FSFUNC"
>SDL_PollEvent</B
></CODE
>(SDL_Event *event);</CODE
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><H2
>Description</H2
><P
>Polls for currently pending events, and returns <SPAN
CLASS="RETURNVALUE"
>1</SPAN
> 
if there are any pending events, or <SPAN
CLASS="RETURNVALUE"
>0</SPAN
> if there 
are none available.  </P
><P
>If <TT
CLASS="PARAMETER"
><I
>event</I
></TT
> is not <TT
CLASS="LITERAL"
>NULL</TT
>, the next 
event is removed from the queue and stored in that area.</P
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>Examples</H2
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>SDL_Event event; /* Event structure */

.
.
.
/* Check for events */
while(SDL_PollEvent(&#38;event)){  /* Loop until there are no events left on the queue */
  switch(event.type){  /* Process the appropiate event type */
    case SDL_KEYDOWN:  /* Handle a KEYDOWN event */         
      printf("Oh! Key press\n");
      break;
    case SDL_MOUSEMOTION:
      .
      .
      .
    default: /* Report an unhandled event */
      printf("I don't know what this event is!\n");
  }
}</PRE
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>SDL_Event</SPAN
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>SDL_WaitEvent</TT
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