view docs/html/time.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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>Chapter 13. Time</H1
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>Table of Contents</B
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><DT
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>SDL_GetTicks</A
>&nbsp;--&nbsp;Get the number of milliseconds since the SDL library initialization.</DT
><DT
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>SDL_Delay</A
>&nbsp;--&nbsp;Wait a specified number of milliseconds before returning.</DT
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>SDL_AddTimer</A
>&nbsp;--&nbsp;Add a timer which will call a callback after the specified number of milliseconds has
elapsed.</DT
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>SDL_RemoveTimer</A
>&nbsp;--&nbsp;Remove a timer which was added with
<A
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>SDL_AddTimer</A
>.</DT
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>SDL_SetTimer</A
>&nbsp;--&nbsp;Set a callback to run after the specified number of milliseconds has
elapsed.</DT
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><P
>SDL provides several cross-platform functions for dealing with time.
It provides a way to get the current time, a way to wait a little while,
and a simple timer mechanism.  These functions give you two ways of moving an
object every x milliseconds:

<P
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>Use a timer callback function.  This may have the bad effect that it runs in a seperate thread or uses alarm signals, but it's easier to implement.</P
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>Or you can get the number of milliseconds passed, and move the object if, for example, 30 ms passed.</P
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>&#13;</P
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