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Date: Fri, 30 Aug 2013 10:43:57 -0800
From: Tim Johnson <tim@akwebsoft.com>
To: "python-list (General)" <python-list@python.org>
Subject: Re: subprocess.Popen instance hangs
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* Jerry Hill <malaclypse2@gmail.com> [130830 07:48]:
> On Fri, Aug 30, 2013 at 11:32 AM, Tim Johnson <tim@akwebsoft.com> wrote:
> >   The objective is to display all output, but to also separate error
> >   messages from normal output.
> 
> I still think you want to use communicate().  Like this:
> 
> p = subprocess.Popen(args,stderr=subprocess.PIPE,stdout=subprocess.PIPE)
> output, err = p.communicate()
> 
> That's it.  No need for a loop, or manually handling the fact that
> stderr and/or stdout could end up with a full buffer and start to
> block.
  The following code :
p = subprocess.Popen(args,stderr=subprocess.PIPE,stdout=subprocess.PIPE)
errmsg,output = p.communicate()
... Hangs
this code :
p = subprocess.Popen(args,stderr=subprocess.PIPE,stdout=subprocess.PIPE)
while 1 :
	output = p.stdout.read()
	if output :
		print(output)
	else : break
... works
-- 
Tim 
tim at tee jay forty nine dot com or akwebsoft dot com
http://www.akwebsoft.com