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  81 >Chapter 8. Events</H1
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  85 ><DT
  86 ><B
  87 >Table of Contents</B
  88 ></DT
  89 ><DT
  90 ><A
  91 HREF="event.html#AEN3691"
  92 >Introduction</A
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  97 >SDL Event Structures.</A
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 100 ><A
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 102 >Event Functions.</A
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 107 CLASS="SECT1"
 108 ><H1
 109 CLASS="SECT1"
 110 ><A
 111 NAME="AEN3691"
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 113 >Introduction</H1
 114 ><P
 115 >Event handling allows your application to receive input from the user. Event handling is initalised (along with video) with a call to:
 116 <PRE
 117 CLASS="PROGRAMLISTING"
 118 >SDL_Init(SDL_INIT_VIDEO);</PRE
 119 >
 120 Internally, SDL stores all the events waiting to be handled in an event queue. Using functions like <A
 121 HREF="sdlpollevent.html"
 122 ><TT
 123 CLASS="FUNCTION"
 124 >SDL_PollEvent</TT
 125 ></A
 126 > and <A
 127 HREF="sdlpeepevents.html"
 128 ><TT
 129 CLASS="FUNCTION"
 130 >SDL_PeepEvents</TT
 131 ></A
 132 > you can observe and handle waiting input events.</P
 133 ><P
 134 >The key to event handling in SDL is the <A
 135 HREF="sdlevent.html"
 136 ><SPAN
 137 CLASS="STRUCTNAME"
 138 >SDL_Event</SPAN
 139 ></A
 140 > union. The event queue itself is composed of a series of <SPAN
 141 CLASS="STRUCTNAME"
 142 >SDL_Event</SPAN
 143 > unions, one for each waiting event. <SPAN
 144 CLASS="STRUCTNAME"
 145 >SDL_Event</SPAN
 146 > unions are read from the queue with the <TT
 147 CLASS="FUNCTION"
 148 >SDL_PollEvent</TT
 149 > function and it is then up to the application to process the information stored with them.</P
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