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><HEAD
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><TITLE
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>Multi-threaded Programming</TITLE
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><META
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NAME="GENERATOR"
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CONTENT="Modular DocBook HTML Stylesheet Version 1.61
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"><LINK
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REL="HOME"
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TITLE="SDL Library Documentation"
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HREF="index.html"><LINK
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REL="UP"
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TITLE="SDL Reference"
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HREF="reference.html"><LINK
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REL="PREVIOUS"
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TITLE="SDL_CDtrack"
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HREF="sdlcdtrack.html"><LINK
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REL="NEXT"
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TITLE="SDL_CreateThread"
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HREF="sdlcreatethread.html"><META
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NAME="KEYWORD"
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CONTENT="threads"><META
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NAME="KEYWORD"
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CONTENT="function"></HEAD
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><BODY
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><TH
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COLSPAN="3"
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ALIGN="center"
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>SDL Library Documentation</TH
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><TR
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WIDTH="10%"
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><A
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HREF="sdlcdtrack.html"
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>Prev</A
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></TD
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VALIGN="bottom"
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><A
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HREF="sdlcreatethread.html"
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>Next</A
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></TD
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></TR
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></TABLE
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><HR
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ALIGN="LEFT"
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WIDTH="100%"></DIV
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><DIV
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CLASS="CHAPTER"
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><H1
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><A
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NAME="THREAD"
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>Chapter 12. Multi-threaded Programming</A
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></H1
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><DIV
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CLASS="TOC"
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><DL
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><DT
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><B
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>Table of Contents</B
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></DT
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><DT
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><A
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HREF="sdlcreatethread.html"
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>SDL_CreateThread</A
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> — Creates a new thread of execution that shares its parent's properties.</DT
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><DT
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><A
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HREF="sdlthreadid.html"
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>SDL_ThreadID</A
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> — Get the 32-bit thread identifier for the current thread.</DT
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><DT
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><A
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HREF="sdlgetthreadid.html"
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>SDL_GetThreadID</A
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> — Get the SDL thread ID of a SDL_Thread</DT
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><DT
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><A
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HREF="sdlwaitthread.html"
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>SDL_WaitThread</A
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> — Wait for a thread to finish.</DT
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><DT
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><A
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HREF="sdlkillthread.html"
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>SDL_KillThread</A
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> — Gracelessly terminates the thread.</DT
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><DT
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><A
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HREF="sdlcreatemutex.html"
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>SDL_CreateMutex</A
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> — Create a mutex</DT
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><DT
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><A
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HREF="sdldestroymutex.html"
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>SDL_DestroyMutex</A
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> — Destroy a mutex</DT
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><DT
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><A
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HREF="sdlmutexp.html"
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>SDL_mutexP</A
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> — Lock a mutex</DT
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><DT
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><A
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HREF="sdlmutexv.html"
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>SDL_mutexV</A
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> — Unlock a mutex</DT
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><DT
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><A
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HREF="sdlcreatesemaphore.html"
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>SDL_CreateSemaphore</A
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> — Creates a new semaphore and assigns an initial value to it.</DT
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><DT
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><A
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HREF="sdldestroysemaphore.html"
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>SDL_DestroySemaphore</A
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> — Destroys a semaphore that was created by <A
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HREF="sdlcreatesemaphore.html"
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>SDL_CreateSemaphore</A
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>.</DT
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><DT
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><A
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HREF="sdlsemwait.html"
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>SDL_SemWait</A
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> — Lock a semaphore and suspend the thread if the semaphore value is zero.</DT
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><DT
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><A
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HREF="sdlsemtrywait.html"
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>SDL_SemTryWait</A
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> — Attempt to lock a semaphore but don't suspend the thread.</DT
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><DT
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><A
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HREF="sdlsemwaittimeout.html"
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>SDL_SemWaitTimeout</A
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> — Lock a semaphore, but only wait up to a specified maximum time.</DT
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><DT
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><A
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HREF="sdlsempost.html"
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>SDL_SemPost</A
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> — Unlock a semaphore.</DT
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><DT
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><A
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HREF="sdlsemvalue.html"
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>SDL_SemValue</A
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> — Return the current value of a semaphore.</DT
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><DT
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><A
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HREF="sdlcreatecond.html"
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>SDL_CreateCond</A
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> — Create a condition variable</DT
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><DT
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><A
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HREF="sdldestroycond.html"
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>SDL_DestroyCond</A
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> — Destroy a condition variable</DT
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><DT
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><A
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HREF="sdlcondsignal.html"
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>SDL_CondSignal</A
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> — Restart a thread wait on a condition variable</DT
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><DT
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><A
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HREF="sdlcondbroadcast.html"
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>SDL_CondBroadcast</A
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> — Restart all threads waiting on a condition variable</DT
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><DT
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><A
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HREF="sdlcondwait.html"
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>SDL_CondWait</A
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> — Wait on a condition variable</DT
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><DT
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><A
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HREF="sdlcondwaittimeout.html"
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>SDL_CondWaitTimeout</A
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> — Wait on a condition variable, with timeout</DT
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></DL
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></DIV
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><P
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>SDL provides functions for creating threads, mutexes, semphores and condition variables.</P
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><P
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>In general, you must be very aware of concurrency and data integrity issues
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when writing multi-threaded programs. Some good guidelines include:
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<P
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></P
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><UL
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><LI
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><P
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>Don't call SDL video/event functions from separate threads</P
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></LI
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><LI
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><P
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>Don't use any library functions in separate threads</P
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></LI
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><LI
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><P
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>Don't perform any memory management in separate threads</P
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></LI
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><LI
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><P
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>Lock global variables which may be accessed by multiple threads</P
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></LI
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><LI
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><P
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>Never terminate threads, always set a flag and wait for them to quit</P
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></LI
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><LI
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><P
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>Think very carefully about all possible ways your code may interact</P
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></LI
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></UL
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></P
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><DIV
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CLASS="NOTE"
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><BLOCKQUOTE
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CLASS="NOTE"
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><P
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><B
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>Note: </B
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>SDL's threading is not implemented on MacOS, due to that lack of preemptive thread support (eck!)</P
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></BLOCKQUOTE
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></DIV
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></DIV
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HREF="sdlcdtrack.html"
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>Prev</A
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>Next</A
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>SDL_CDtrack</TD
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WIDTH="34%"
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>Up</A
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>SDL_CreateThread</TD
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