Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > comp.lang.python > #103475

Re: [Python-ideas] How the heck does async/await work in Python 3.5

Show key headers only | View raw

On Thu, 25 Feb 2016 10:00:29 +1300, Gregory Ewing
<greg.ewing@canterbury.ac.nz> declaimed the following:

>?? wrote:
>> Suppose io_operation() takes 3 seconds, then how can I write something like
>> 
>> future = io_operation()
>> print('Start')
>> time.sleep(1)
>> print('Something')
>> time.sleep(2)
>> print(future.result())
>> 
>> that print 'Start' immediately and the result of io_operation() 3 seconds
>> later.
>
>Yes, Python can do this, but you probably need to use real
>threads. The only exception would be if io_operation() were
>something you could fire off with a single system call that's
>guaranteed not to block, and then wait for the result later.
>Opportunities for things like that are rare in unix.
>(Windows might be different, I'm not sure.)
>
	But was common under VMS
https://en.wikipedia.org/wiki/QIO

	I believe Windows is supposed to be similar, but QIO status words and
event flags were understandable to me (and close match to AmigaOS too <G>);
Windows somehow treats the I/O channel itself as the waitable object (well,
looks like one embeds it into the I/O call -- but has to create the channel
in "overlapped" mode where VMS differentiated on the I/O call itself: QIO
vs QIOW; Amiga differentiated with DoIO and SendIO)
https://msdn.microsoft.com/en-us/library/windows/desktop/ms686358%28v=vs.85%29.aspx

http://wiki.amigaos.net/wiki/Exec_Device_I/O#Synchronous_vs._Asynchronous_Requests
-- 
	Wulfraed                 Dennis Lee Bieber         AF6VN
    wlfraed@ix.netcom.com    HTTP://wlfraed.home.netcom.com/

Back to comp.lang.python | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread

Thread

How the heck does async/await work in Python 3.5 Mark Lawrence <breamoreboy@yahoo.co.uk> - 2016-02-17 22:08 +0000
  Re: How the heck does async/await work in Python 3.5 Steven D'Aprano <steve@pearwood.info> - 2016-02-20 13:36 +1100
    Re: How the heck does async/await work in Python 3.5 Rustom Mody <rustompmody@gmail.com> - 2016-02-19 21:24 -0800
      Re: How the heck does async/await work in Python 3.5 Rustom Mody <rustompmody@gmail.com> - 2016-02-19 21:34 -0800
        Re: How the heck does async/await work in Python 3.5 Paul Rubin <no.email@nospam.invalid> - 2016-02-19 22:44 -0800
          Re: How the heck does async/await work in Python 3.5 Steven D'Aprano <steve@pearwood.info> - 2016-02-21 18:17 +1100
            Re: How the heck does async/await work in Python 3.5 Paul Rubin <no.email@nospam.invalid> - 2016-02-20 23:34 -0800
      Re: How the heck does async/await work in Python 3.5 Ian Kelly <ian.g.kelly@gmail.com> - 2016-02-20 00:48 -0700
      Re: How the heck does async/await work in Python 3.5 Chris Angelico <rosuav@gmail.com> - 2016-02-20 18:57 +1100
      Re: How the heck does async/await work in Python 3.5 Ian Kelly <ian.g.kelly@gmail.com> - 2016-02-20 01:14 -0700
      Re: How the heck does async/await work in Python 3.5 Chris Angelico <rosuav@gmail.com> - 2016-02-20 19:49 +1100
      Re: How the heck does async/await work in Python 3.5 Ian Kelly <ian.g.kelly@gmail.com> - 2016-02-20 02:11 -0700
      Re: How the heck does async/await work in Python 3.5 Ian Kelly <ian.g.kelly@gmail.com> - 2016-02-20 02:21 -0700
    Re: How the heck does async/await work in Python 3.5 Christian Gollwitzer <auriocus@gmx.de> - 2016-02-20 07:53 +0100
      Re: How the heck does async/await work in Python 3.5 "Sven R. Kunze" <srkunze@mail.de> - 2016-02-22 23:16 +0100
      Re: How the heck does async/await work in Python 3.5 Ian Kelly <ian.g.kelly@gmail.com> - 2016-02-22 17:48 -0700
      Re: How the heck does async/await work in Python 3.5 "Sven R. Kunze" <srkunze@mail.de> - 2016-02-23 17:50 +0100
      Re: How the heck does async/await work in Python 3.5 Ian Kelly <ian.g.kelly@gmail.com> - 2016-02-23 10:37 -0700
      Re: How the heck does async/await work in Python 3.5 "Sven R. Kunze" <srkunze@mail.de> - 2016-02-23 20:42 +0100
      Re: How the heck does async/await work in Python 3.5 "Sven R. Kunze" <srkunze@mail.de> - 2016-02-23 22:05 +0100
      Re: [Python-ideas] How the heck does async/await work in Python 3.5 "Joao S. O. Bueno" <jsbueno@python.org.br> - 2016-02-23 18:25 -0300
      Re: [Python-ideas] How the heck does async/await work in Python 3.5 Paul Moore <p.f.moore@gmail.com> - 2016-02-24 09:59 +0000
      Re: [Python-ideas] How the heck does async/await work in Python 3.5 Victor Stinner <victor.stinner@gmail.com> - 2016-02-24 11:01 +0100
      Re: [Python-ideas] How the heck does async/await work in Python 3.5 王珺 <wjun77@gmail.com> - 2016-02-24 18:40 +0800
        Re: [Python-ideas] How the heck does async/await work in Python 3.5 Gregory Ewing <greg.ewing@canterbury.ac.nz> - 2016-02-25 10:00 +1300
          Re: [Python-ideas] How the heck does async/await work in Python 3.5 王珺 <wjun77@gmail.com> - 2016-02-25 08:40 +0800
          Re: [Python-ideas] How the heck does async/await work in Python 3.5 Dennis Lee Bieber <wlfraed@ix.netcom.com> - 2016-02-24 20:37 -0500
      Re: [Python-ideas] How the heck does async/await work in Python 3.5 Tem Pl <rtempl31@gmail.com> - 2016-02-24 06:39 -0800
        Re: [Python-ideas] How the heck does async/await work in Python 3.5 Marko Rauhamaa <marko@pacujo.net> - 2016-02-24 17:23 +0200
          Re: [Python-ideas] How the heck does async/await work in Python 3.5 Ian Kelly <ian.g.kelly@gmail.com> - 2016-02-24 08:41 -0700
            Re: [Python-ideas] How the heck does async/await work in Python 3.5 Marko Rauhamaa <marko@pacujo.net> - 2016-02-24 18:13 +0200
              Re: [Python-ideas] How the heck does async/await work in Python 3.5 Ian Kelly <ian.g.kelly@gmail.com> - 2016-02-24 09:47 -0700

csiph-web