1<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> 2<html> 3 4<head> 5<META http-equiv="Content-Type" content="text/html; charset=windows-1252"> 6<META name="GENERATOR" content="Microsoft FrontPage 5.0"> 7<META http-equiv="Content-Style-Type" content="text/css"> 8<LINK rel="stylesheet" type="text/css" href="../../CSS/revolution.css"> 9<title>OSSetIdleFunction</title> 10</head> 11 12<body> 13 14<h1>OSSetIdleFunction</h1> 15 16<h2>C Specification</h2> 17 18<dl> 19<dd><pre><code>#include <revolution/os.h></code></pre> 20 </dd> 21<dd><pre>OSThread* OSSetIdleFunction( OSIdleFunction idleFunction, 22void* param, 23void* stack, 24u32 stackSize );</pre> 25 </dd> 26</dl> 27<h2>Arguments</h2> 28<TABLE border="1" cellpadding="3" cellspacing="0.1"> 29 <tr> 30<TD width="120" bgcolor="#ffffe8"><i><b><code><STRONG><EM><CODE>idleFunction</CODE></EM></STRONG></code></b></i></TD> 31<TD width="520">Pointer to the function to execute. Specify a <CODE>NULL</CODE> pointer to cancel the current idle function.</TD> 32 </tr> 33 <tr> 34<TD width="120" bgcolor="#ffffe8"><i><b><code><STRONG><EM><CODE>param</CODE></EM></STRONG></code></b></i></TD> 35<TD width="520">Arguments to pass to the function.</TD> 36 </tr> 37 <tr> 38<TD width="120" bgcolor="#ffffe8"><i><b><code><STRONG><EM><CODE>stack</CODE></EM></STRONG></code></b></i></TD> 39<TD width="520">Stack used for idle functions.</TD> 40 </tr> 41 <tr> 42<TD width="120" bgcolor="#ffffe8"><i><b><code><STRONG><EM><CODE>stackSize</CODE></EM></STRONG></code></b></i></TD> 43<TD width="520">Stack size in bytes.</TD> 44 </tr> 45</TABLE> 46<h2>Return Values</h2> 47<P>Pointer to <STRONG><EM><CODE>OSThread</CODE></EM></STRONG> used for executing the specified idle functions.</P> 48<H2>Description</H2> 49<P>Creates a background thread that will execute while the game main loop is idle. In other words, the operating system will execute <STRONG><EM><CODE>idleFunction</CODE></EM></STRONG> while the game main loop is waiting for the <a href="../../vi/VIWaitForRetrace.html"><code>VIWaitForRetrace</code></a> function to return.</P> 50<P>The return value of the <a href="OSGetIdleFunction.html"><code>OSGetIdleFunction</code></a> function can be used to determine if the idle function has completed. If the background thread that this function creates is still active, a call to this function fails and returns <code>NULL</code>.</P> 51<P>This function is intended to provide convenience for creating background tasks without worrying about thread management. If more than one background task is required, use the <code><a href="OSCreateThread.html">OSCreateThread</a></code> function instead.</P> 52<P>The OS will write a magic word (OS_THREAD_STACK_MAGIC) into the last word of the stack. Stacks grow downward, so the magic word will be at the lowest address. The <code><a href="OSCheckActiveThreads.html">OSCheckActiveThreads</a> </code> function will check to ensure that the magic word remains intact when it is invoked.</P> 53 54 55 56<h2>See Also</h2> 57 58<p><a href="OSGetIdleFunction.html"><code>OSGetIdleFunction</code></a>, <code><a href="../../vi/VIWaitForRetrace.html">VIWaitForRetrace</a>,<a href="OSCheckActiveThreads.html">OSCheckActiveThreads</a></code></p> 59<H2>Revision History</H2> 60<P>03/01/2006 Initial version.</P> 61</body> 62</html>