Re: Subprocess puzzle and two questions

From	Tim Roberts <timr@probo.com>
Newsgroups	comp.lang.python
Subject	Re: Subprocess puzzle and two questions
Date	2012-11-13 23:17 -0800
Organization	Providenza & Boekelheide, Inc.
Message-ID	<s0h6a89a5pem8sd0u78adu6of2bb04j4e6@4ax.com> (permalink)
References	<mailman.3664.1352867713.27098.python-list@python.org>

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wrw@mac.com wrote:
>...
>However, if I try the same operation in the python interpreter using subprocess.Popen like so:
>
>>>> import subprocess
>>>> result = subprocess.Popen(['time', 'nslookup', 'www.es.net', '8.8.4.4'], shell = False, stdout = subprocess.PIPE, stderr = subprocess.PIPE).communicate()
>>>> print result
>('Server:\t\t8.8.4.4\nAddress:\t8.8.4.4#53\n\nNon-authoritative answer:\nwww.es.net\tcanonical name = www3.es.net.\nName:\twww3.es.net\nAddress: 128.55.22.201\n\n', '        0.06 real         0.00 user         0.00 sys\n')
>
>And the timing information I'm after has been truncated to two digits after the decimal.  It appears that Popen is applying a default format. 

No, that's silly.  A few minutes thought should have told you that.  In
your standalone test, you are getting the "time" command that is built in
to bash.  In the subprocess example, you've specified "shell = False", so
you are using the external "time" command (/usr/bin/time in my system), and
that command has a different output format.  The csh "time" command is
different yet again.

>1) how can I recover that third digit from the subprocess?

Do you actually believe that the third decimal place has any meaning at
all?  It doesn't.
-- 
Tim Roberts, timr@probo.com
Providenza & Boekelheide, Inc.

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Subprocess puzzle and two questions wrw@mac.com - 2012-11-13 22:34 -0500
  Re: Subprocess puzzle and two questions Roy Smith <roy@panix.com> - 2012-11-13 23:41 -0500
    Re: Subprocess puzzle and two questions William Ray Wing <wrw@mac.com> - 2012-11-14 00:03 -0500
      Re: Subprocess puzzle and two questions Roy Smith <roy@panix.com> - 2012-11-14 09:22 -0500
        Re: Subprocess puzzle and two questions Chris Angelico <rosuav@gmail.com> - 2012-11-15 01:40 +1100
          Re: Subprocess puzzle and two questions roy@panix.com (Roy Smith) - 2012-11-14 11:20 -0500
            Re: Subprocess puzzle and two questions Chris Angelico <rosuav@gmail.com> - 2012-11-15 08:54 +1100
              Re: Subprocess puzzle and two questions Roy Smith <roy@panix.com> - 2012-11-14 20:49 -0500
                Re: Subprocess puzzle and two questions Chris Angelico <rosuav@gmail.com> - 2012-11-15 13:04 +1100
                Re: Subprocess puzzle and two questions Roy Smith <roy@panix.com> - 2012-11-14 21:10 -0500
                Re: Subprocess puzzle and two questions Chris Angelico <rosuav@gmail.com> - 2012-11-15 13:21 +1100
                Re: Subprocess puzzle and two questions Dave Angel <d@davea.name> - 2012-11-14 21:55 -0500
                Re: Subprocess puzzle and two questions Kushal Kumaran <kushal.kumaran+python@gmail.com> - 2012-11-15 10:23 +0530
                Re: Subprocess puzzle and two questions Nobody <nobody@nowhere.com> - 2012-11-15 22:54 +0000
                Re: Subprocess puzzle and two questions Roy Smith <roy@panix.com> - 2012-11-15 20:07 -0500
                Re: Subprocess puzzle and two questions Nobody <nobody@nowhere.com> - 2012-11-17 00:17 +0000
              DNS from Python (was Re: Subprocess puzzle and two questions) aahz@pythoncraft.com (Aahz) - 2012-11-14 21:42 -0800
        Re: Subprocess puzzle and two questions wrw@mac.com - 2012-11-14 09:37 -0500
  Re: Subprocess puzzle and two questions Tim Roberts <timr@probo.com> - 2012-11-13 23:17 -0800

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