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select(sock) indicates not-ready, but sock.recv does not block

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From Nikolaus Rath <Nikolaus@rath.org>
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Subject select(sock) indicates not-ready, but sock.recv does not block
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Date Sun, 16 Feb 2014 22:35:22 -0800
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Hello,

I have a problem with using select. I can reliably reproduce a situation
where select.select((sock.fileno(),), (), (), 0) returns ((),(),())
(i.e., no data ready for reading), but an immediately following
sock.recv() returns data without blocking.

I am pretty sure that this is not a race condition. The behavor is 100%
reproducible, the program is single threaded, and even waiting for 10
seconds before the select() call does not change the result.

I'm running Python 3.3.3 under Linux 3.12.

Has anyone an idea what might be going wrong here?

Thanks,
-Nikolaus

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Thread

select(sock) indicates not-ready, but sock.recv does not block Nikolaus Rath <Nikolaus@rath.org> - 2014-02-16 22:35 -0800
  Re: select(sock) indicates not-ready, but sock.recv does not block Roy Smith <roy@panix.com> - 2014-02-17 08:04 -0500

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