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I've made so many changes I don't dare continue until I check the current stuff in. /test/testatomic.c performs absolutely basic tests to show that the function work as expected. Need a second test to do more detailed tests. /include/SDL_atomic.h provides declarations for all included functions. /src/atomic/linux/SDL_atomic.c provided all the functions. On a generic built the 64 bit functions work, but they are emulated. On a build for -march=pentium and above the 64 bit functions use native instructions /src/atomic/dummy/SDL_atomic.c emulates all the operations using SDL_mutex.h. /src/atomic/win32/SDL_atomic.c is a copy of dummy /src/atomic/macosx/SDL_atomic.s is a copy of dummy These versions of SDL_atomic.c provide a frame work for building the library with a mixture of native and emulated functions. This allows the whole library to be provided on all platforms. (I hope.) I hope this fits with the SDL philosophy of either providing a common subset or emulating when the platform is missing a feature. I have not added dummy, macosx, or win32 to the build. They are there as place holders for future work. I have modified congifure.in to compile sources in /src/atomic/linux. (The SDL configure.in file is an amazing piece of work and I hope I didn't mess it up. :-)
author Bob Pendleton <bob@pendleton.com>
date Mon, 29 Jun 2009 19:54:43 +0000
parents 355632dca928
children
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<HTML
><HEAD
><TITLE
>SDL_SetTimer</TITLE
><META
NAME="GENERATOR"
CONTENT="Modular DocBook HTML Stylesheet Version 1.76b+
"><LINK
REL="HOME"
TITLE="SDL Library Documentation"
HREF="index.html"><LINK
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TITLE="Time"
HREF="time.html"><LINK
REL="PREVIOUS"
TITLE="SDL_RemoveTimer"
HREF="sdlremovetimer.html"></HEAD
><BODY
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>SDL Library Documentation</TH
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><HR
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WIDTH="100%"></DIV
><H1
><A
NAME="SDLSETTIMER"
></A
>SDL_SetTimer</H1
><DIV
CLASS="REFNAMEDIV"
><A
NAME="AEN8557"
></A
><H2
>Name</H2
>SDL_SetTimer&nbsp;--&nbsp;Set a callback to run after the specified number of milliseconds has
elapsed.</DIV
><DIV
CLASS="REFSYNOPSISDIV"
><A
NAME="AEN8560"
></A
><H2
>Synopsis</H2
><DIV
CLASS="FUNCSYNOPSIS"
><A
NAME="AEN8561"
></A
><P
></P
><PRE
CLASS="FUNCSYNOPSISINFO"
>#include "SDL.h"</PRE
><P
><CODE
><CODE
CLASS="FUNCDEF"
>int <B
CLASS="FSFUNC"
>SDL_SetTimer</B
></CODE
>(Uint32 interval, SDL_TimerCallback callback);</CODE
></P
><P
></P
></DIV
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="SDLTIMERCALLBACK"
></A
><H2
>Callback</H2
><P
>/* Function prototype for the timer callback function */
typedef Uint32 (*SDL_TimerCallback)(Uint32 interval);</P
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN8570"
></A
><H2
>Description</H2
><P
>Set a callback to run after the specified number of milliseconds has
elapsed. The callback function is passed the current timer interval
and returns the next timer interval.  If the returned value is the
same as the one passed in, the periodic alarm continues, otherwise a
new alarm is scheduled.</P
><P
>To cancel a currently running timer, call
<TT
CLASS="FUNCTION"
>SDL_SetTimer(0, NULL);</TT
></P
><P
>The timer callback function may run in a different thread than your
main constant, and so shouldn't call any functions from within itself.</P
><P
>The maximum resolution of this timer is 10 ms, which means that if
you request a 16 ms timer, your callback will run approximately 20 ms
later on an unloaded system.  If you wanted to set a flag signaling
a frame update at 30 frames per second (every 33 ms), you might set a
timer for 30 ms (see example below).</P
><P
>If you use this function, you need to pass <TT
CLASS="LITERAL"
>SDL_INIT_TIMER</TT
>
to <TT
CLASS="FUNCTION"
>SDL_Init()</TT
>.</P
><DIV
CLASS="NOTE"
><BLOCKQUOTE
CLASS="NOTE"
><P
><B
>Note: </B
>This function is kept for compatibility but has been superseded
by the new timer functions
<A
HREF="sdladdtimer.html"
>SDL_AddTimer</A
> and
<A
HREF="sdlremovetimer.html"
>SDL_RemoveTimer</A
> which support
multiple timers.</P
></BLOCKQUOTE
></DIV
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN8584"
></A
><H2
>Examples</H2
><P
><PRE
CLASS="PROGRAMLISTING"
>SDL_SetTimer((33/10)*10, my_callback);</PRE
></P
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN8588"
></A
><H2
>See Also</H2
><P
><A
HREF="sdladdtimer.html"
><TT
CLASS="FUNCTION"
>SDL_AddTimer</TT
></A
></P
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