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From: Marko Rauhamaa <marko@pacujo.net>
Newsgroups: comp.lang.python
Subject: Re: select.poll and ppoll
Date: Sun, 25 Oct 2015 21:21:48 +0200
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Steven D'Aprano <steve+comp.lang.python@pearwood.info>:

> On Thursday 22 October 2015 22:18, Marko Rauhamaa wrote:
>> The standard, classic way to solve the race condition is to replace
>> the "signaled" flag with an internal pipe. The signal handler writes
>> a byte into the pipe and select.poll() wakes up when the pipe becomes
>> readable. IOW, ppoll() and pselect() are not needed.
>
> [...]
>
> I will discuss with my colleague and see if this solves his problem.

Note also that "newer" Linux kernels (2.6.25 and up) have a file
descriptor type, signalfd, that simplifies the idiom slightly.


Marko