Re: Multiple threads

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From	Christian Heimes <lists@cheimes.de>
Subject	Re: Multiple threads
Date	Wed, 16 Nov 2011 16:01:15 +0100
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Am 16.11.2011 14:48, schrieb Eduardo Oliva:
> Hello, I have a py script that reads for all "m2ts" video files and convert them to "mpeg" using ffmpeg with command line.
> 
> What I want to do is:
> 
>   I need my script to run 2 separated threads, and then when the first has finished, starts the next one....but no more than 2 threads.
>   I know that Semaphores would help with that.
>   But the problem here is to know when the thread has finished its job, to release the semaphore and start another thread.

I suggest a slight different approach: use a queue [1] and create two
worker threads that consume the queue. You don't need multiprocessing
because you are already using multiple processes here (one Python and
two ffmpeg processes).

Christian

[1] http://docs.python.org/library/queue.html

Thread

Multiple threads Eduardo Oliva <dutche@gmail.com> - 2011-11-16 05:48 -0800
  Re: Multiple threads Chris Angelico <rosuav@gmail.com> - 2011-11-17 00:55 +1100
  Re: Multiple threads Henrik Faber <hfaber@invalid.net> - 2011-11-16 15:07 +0100
  Re: Multiple threads Christian Heimes <lists@cheimes.de> - 2011-11-16 16:01 +0100
  Re: Multiple threads Thomas Rachel <nutznetz-0c1b6768-bfa9-48d5-a470-7603bd3aa915@spamschutz.glglgl.de> - 2011-11-16 17:45 +0100
    Re: Multiple threads Dennis Lee Bieber <wlfraed@ix.netcom.com> - 2011-11-16 16:38 -0800
  Re: Multiple threads Dave Angel <d@davea.name> - 2011-11-16 12:27 -0500
  Re: Multiple threads Michael Hunter <tahoemph@gmail.com> - 2011-11-16 09:55 -0800
  Re: Multiple threads Dave Angel <d@davea.name> - 2011-11-16 13:06 -0500
  Re: Multiple threads Dave Angel <d@davea.name> - 2011-11-16 13:30 -0500
  Re: Multiple threads Miki Tebeka <miki.tebeka@gmail.com> - 2011-11-16 12:50 -0800

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