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Date: Wed, 3 Aug 2011 12:04:42 +0200
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Subject: Re: python doesn't allow descriptors > 63 in select
From: Reini Urban <rurban AT x-ray DOT at>
To: cygwin AT cygwin DOT com
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2011/8/3 Corinna Vinschen:
>  $ python sel.py
>  socket opened with fd 3
>  socket opened with fd 4
>  socket opened with fd 5
>  [...]
>  socket opened with fd 62
>  socket opened with fd 63
>  socket opened with fd 64
>  socket opened with fd 64
>  Traceback (most recent call last):
>    File "test.py", line 10, in <module>
>      select(ins, [], [], 0)
>  ValueError: filedescriptor out of range in select()
>
> I debugged this and it turns out that python does not call Cygwin's
> select function anymore, as soon as there's a file descriptor in the
> set which is >= 64.

I have a similar limitation in postgresql, and I heard that this is
based on a windows limitation, not any predefined constant.
In postgresql I can max fork 63 worker childs, tested by a configure probe.
-- 
Reini

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