Changes to Threads between r3 and r4
'''Threads and Threading'''
Threads are a method of dividing a process or program so that different parts of it may execute (or may seem to execute) in parallel, while still sharing the same address space.
Threads are a useful technique for making an otherwise complicated procedure where disparate functions need to be performed without much (but usually with some) coordination. For example, many graphical user interface systems are threaded so that the process can handle the User Interface and the Primary Function Code in logically distinct units while still being able to have the two interface with each other through a simple interface (memory).
A parallel concept (but perhaps not obviously so) to threads is [Events].
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'''Types of Threading''' --> '''Types of Threading''' ''([Threading Models])''
There are two types of threading: [Cooperative Threading] and [Preemptive Threading]
If you want [Cooperative], [Protothreads] is by far the most portable ([GNU Pth], for example, won't run under [win32]).
If you want [Preemptive], I'd go with POSIX Threads ([pthreads]), and use a wrapper (library, or, if you can -- a simple header) for places that don't support POSIX Threads (notably [Win32] without "Services for Unix" installed on the client).
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'''More About Events'''
Doctor John Ousterhout (principal designer of the [Tcl] language) wrote a paper about [Events] called "Why Threads are a Bad Idea (for most purposes)" [http://home.pacbell.net/ouster/threads.pdf] [http://www.rkeene.org/projects/info/resources/threads/papers/threads.pdf]
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'''Give Me an Example'''
The same program written using various threading techniques (the same style is used for clarity, even if it causes inefficiency (i.e., by not using pthread_join)):
* [Cheap Threads]: http://www.rkeene.org/projects/info/resources/threads/test1-ct.c
* [Libfiber]: http://www.rkeene.org/projects/info/resources/threads/test1-lf.c
* [Protothreads]: http://www.rkeene.org/projects/info/resources/threads/test1-pt.c
* [GNU Pth]: http://www.rkeene.org/projects/info/resources/threads/test1-pth.c
* [PThreads]: http://www.rkeene.org/projects/info/resources/threads/test1-pthread.c
* [PThreads] with [Win32] Wrapper support: http://www.rkeene.org/projects/info/resources/threads/test1-pthread-emul.c
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'''[Win32] [Pthreads] information'''
* http://world.std.com/~jmhart/opensource.htm [http://www.rkeene.org/projects/info/resources/threads/pthread-emul/opensource.htm]
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'''Other information'''
* Information about [Tcl and Threads]
* [Jonathan Mayo] also wrote a simple threading system called [Orangetide's Tiny Threads]
Only in r3
Only in r4 --> Modified slightly between r3 and r4