Mercurial > sdl-ios-xcode

view docs/html/thread.html @ 855:aa4ac9e65d92

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
I noticed MacOSX SDL sets up working directory to parent of executable. On BeOS is should setup it the same way, but it only does when Tracker wasn't restarted. I checked code and it looks like a hack to me :( It looks for env variable and than comapres it to default when OpenTracker was started after boot, and wasn't restarted. That's probably ok, for that exact case. Unfortunetly that variable isn't always like that. For example, after Tracker crashes and is restarted, env variable most probably is different (depends on how Tracker was restarted, by what application, etc... for example: i have launcher application from which i can restart Tracker, and after that nev variable points to that application's directory, not Tracker's).
author Sam Lantinga <slouken@libsdl.org>
date Tue, 24 Feb 2004 18:58:40 +0000
parents 355632dca928
children f12379c41042
line wrap: on
line source

<HTML
><HEAD
><TITLE
>Multi-threaded Programming</TITLE
><META
NAME="GENERATOR"
CONTENT="Modular DocBook HTML Stylesheet Version 1.76b+
"><LINK
REL="HOME"
TITLE="SDL Library Documentation"
HREF="index.html"><LINK
REL="UP"
TITLE="SDL Reference"
HREF="reference.html"><LINK
REL="PREVIOUS"
TITLE="SDL_CDtrack"
HREF="sdlcdtrack.html"><LINK
REL="NEXT"
TITLE="SDL_CreateThread"
HREF="sdlcreatethread.html"><META
NAME="KEYWORD"
CONTENT="threads"><META
NAME="KEYWORD"
CONTENT="function"></HEAD
><BODY
CLASS="CHAPTER"
BGCOLOR="#FFF8DC"
TEXT="#000000"
LINK="#0000ee"
VLINK="#551a8b"
ALINK="#ff0000"
><DIV
CLASS="NAVHEADER"
><TABLE
SUMMARY="Header navigation table"
WIDTH="100%"
BORDER="0"
CELLPADDING="0"
CELLSPACING="0"
><TR
><TH
COLSPAN="3"
ALIGN="center"
>SDL Library Documentation</TH
></TR
><TR
><TD
WIDTH="10%"
ALIGN="left"
VALIGN="bottom"
><A
HREF="sdlcdtrack.html"
ACCESSKEY="P"
>Prev</A
></TD
><TD
WIDTH="80%"
ALIGN="center"
VALIGN="bottom"
></TD
><TD
WIDTH="10%"
ALIGN="right"
VALIGN="bottom"
><A
HREF="sdlcreatethread.html"
ACCESSKEY="N"
>Next</A
></TD
></TR
></TABLE
><HR
ALIGN="LEFT"
WIDTH="100%"></DIV
><DIV
CLASS="CHAPTER"
><H1
><A
NAME="THREAD"
></A
>Chapter 12. Multi-threaded Programming</H1
><DIV
CLASS="TOC"
><DL
><DT
><B
>Table of Contents</B
></DT
><DT
><A
HREF="sdlcreatethread.html"
>SDL_CreateThread</A
>&nbsp;--&nbsp;Creates a new thread of execution that shares its parent's properties.</DT
><DT
><A
HREF="sdlthreadid.html"
>SDL_ThreadID</A
>&nbsp;--&nbsp;Get the 32-bit thread identifier for the current thread.</DT
><DT
><A
HREF="sdlgetthreadid.html"
>SDL_GetThreadID</A
>&nbsp;--&nbsp;Get the SDL thread ID of a SDL_Thread</DT
><DT
><A
HREF="sdlwaitthread.html"
>SDL_WaitThread</A
>&nbsp;--&nbsp;Wait for a thread to finish.</DT
><DT
><A
HREF="sdlkillthread.html"
>SDL_KillThread</A
>&nbsp;--&nbsp;Gracelessly terminates the thread.</DT
><DT
><A
HREF="sdlcreatemutex.html"
>SDL_CreateMutex</A
>&nbsp;--&nbsp;Create a mutex</DT
><DT
><A
HREF="sdldestroymutex.html"
>SDL_DestroyMutex</A
>&nbsp;--&nbsp;Destroy a mutex</DT
><DT
><A
HREF="sdlmutexp.html"
>SDL_mutexP</A
>&nbsp;--&nbsp;Lock a mutex</DT
><DT
><A
HREF="sdlmutexv.html"
>SDL_mutexV</A
>&nbsp;--&nbsp;Unlock a mutex</DT
><DT
><A
HREF="sdlcreatesemaphore.html"
>SDL_CreateSemaphore</A
>&nbsp;--&nbsp;Creates a new semaphore and assigns an initial value to it.</DT
><DT
><A
HREF="sdldestroysemaphore.html"
>SDL_DestroySemaphore</A
>&nbsp;--&nbsp;Destroys a semaphore that was created by <A
HREF="sdlcreatesemaphore.html"
>SDL_CreateSemaphore</A
>.</DT
><DT
><A
HREF="sdlsemwait.html"
>SDL_SemWait</A
>&nbsp;--&nbsp;Lock a semaphore and suspend the thread if the semaphore value is zero.</DT
><DT
><A
HREF="sdlsemtrywait.html"
>SDL_SemTryWait</A
>&nbsp;--&nbsp;Attempt to lock a semaphore but don't suspend the thread.</DT
><DT
><A
HREF="sdlsemwaittimeout.html"
>SDL_SemWaitTimeout</A
>&nbsp;--&nbsp;Lock a semaphore, but only wait up to a specified maximum time.</DT
><DT
><A
HREF="sdlsempost.html"
>SDL_SemPost</A
>&nbsp;--&nbsp;Unlock a semaphore.</DT
><DT
><A
HREF="sdlsemvalue.html"
>SDL_SemValue</A
>&nbsp;--&nbsp;Return the current value of a semaphore.</DT
><DT
><A
HREF="sdlcreatecond.html"
>SDL_CreateCond</A
>&nbsp;--&nbsp;Create a condition variable</DT
><DT
><A
HREF="sdldestroycond.html"
>SDL_DestroyCond</A
>&nbsp;--&nbsp;Destroy a condition variable</DT
><DT
><A
HREF="sdlcondsignal.html"
>SDL_CondSignal</A
>&nbsp;--&nbsp;Restart a thread wait on a condition variable</DT
><DT
><A
HREF="sdlcondbroadcast.html"
>SDL_CondBroadcast</A
>&nbsp;--&nbsp;Restart all threads waiting on a condition variable</DT
><DT
><A
HREF="sdlcondwait.html"
>SDL_CondWait</A
>&nbsp;--&nbsp;Wait on a condition variable</DT
><DT
><A
HREF="sdlcondwaittimeout.html"
>SDL_CondWaitTimeout</A
>&nbsp;--&nbsp;Wait on a condition variable, with timeout</DT
></DL
></DIV
><P
>SDL provides functions for creating threads, mutexes, semphores and condition variables.</P
><P
>In general, you must be very aware of concurrency and data integrity issues
when writing multi-threaded programs.  Some good guidelines include:
<P
></P
><UL
><LI
><P
>Don't call SDL video/event functions from separate threads</P
></LI
><LI
><P
>Don't use any library functions in separate threads</P
></LI
><LI
><P
>Don't perform any memory management in separate threads</P
></LI
><LI
><P
>Lock global variables which may be accessed by multiple threads</P
></LI
><LI
><P
>Never terminate threads, always set a flag and wait for them to quit</P
></LI
><LI
><P
>Think very carefully about all possible ways your code may interact</P
></LI
></UL
></P
><DIV
CLASS="NOTE"
><BLOCKQUOTE
CLASS="NOTE"
><P
><B
>Note: </B
>SDL's threading is not implemented on MacOS, due to that lack of preemptive thread support (MacOS X dos nt suffer from this problem)</P
></BLOCKQUOTE
></DIV
></DIV
><DIV
CLASS="NAVFOOTER"
><HR
ALIGN="LEFT"
WIDTH="100%"><TABLE
SUMMARY="Footer navigation table"
WIDTH="100%"
BORDER="0"
CELLPADDING="0"
CELLSPACING="0"
><TR
><TD
WIDTH="33%"
ALIGN="left"
VALIGN="top"
><A
HREF="sdlcdtrack.html"
ACCESSKEY="P"
>Prev</A
></TD
><TD
WIDTH="34%"
ALIGN="center"
VALIGN="top"
><A
HREF="index.html"
ACCESSKEY="H"
>Home</A
></TD
><TD
WIDTH="33%"
ALIGN="right"
VALIGN="top"
><A
HREF="sdlcreatethread.html"
ACCESSKEY="N"
>Next</A
></TD
></TR
><TR
><TD
WIDTH="33%"
ALIGN="left"
VALIGN="top"
>SDL_CDtrack</TD
><TD
WIDTH="34%"
ALIGN="center"
VALIGN="top"
><A
HREF="reference.html"
ACCESSKEY="U"
>Up</A
></TD
><TD
WIDTH="33%"
ALIGN="right"
VALIGN="top"
>SDL_CreateThread</TD
></TR
></TABLE
></DIV
></BODY
></HTML
>