Path: csiph.com!fu-berlin.de!uni-berlin.de!not-for-mail
From: Terry Reedy <tjreedy@udel.edu>
Newsgroups: comp.lang.python
Subject: Re: cross platform alternative for signal.SIGALRM?
Date: Thu, 12 Nov 2015 05:15:52 -0500
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Xref: csiph.com comp.lang.python:98690

On 11/12/2015 2:37 AM, Chris Angelico wrote:
> On Thu, Nov 12, 2015 at 5:43 PM, Christian Gollwitzer <auriocus@gmx.de> wrote:
>> My understanding of async is that it creates an event loop. In which case
>> the loop has no chance to run within a block of code that computes anything,
>> is that correct?
>
> This is correct. At its simplest, asynchronous code is an abstraction
> over the select() call,

True on Unix-derived systems, where 'select' includes the various 
derivatives.  It is also an abstraction over the Windows completion 
calls, which are quite different.  The latter is why one must generally 
use a different event loop on Windows.  The point is that asyncio 
provides an *abstraction* such that after choosing the event loop, the 
rest of one's code is os-agnostic.

-- 
Terry Jan Reedy