getting a string as the return value from a system command

[Robert Kern]

On 2010-04-18 03:13 , TomF wrote:
> On 2010-04-16 12:06:13 -0700, Catherine Moroney said:
>
>> Hello,
>>
>> I want to call a system command (such as uname) that returns a string,
>> and then store that output in a string variable in my python program.
>>
>> What is the recommended/most-concise way of doing this?
>>
>> I could always create a temporary file, call the "subprocess.Popen"
>> module with the temporary file as the stdout argument, and then
>> re-open that temporary file and read in its contents. This seems
>> to be awfully long way of doing this, and I was wondering about
>> alternate ways of accomplishing this task.
>>
>> In pseudocode, I would like to be able to do something like:
>> hostinfo = subprocess.Popen("uname -srvi") and have hostinfo
>> be a string containing the result of issuing the uname command.
>
> Here is the way I do it:
>
> import os
> hostinfo = os.popen("uname -srvi").readline().strip()
>
> (I add a strip() call to get rid of the trailing newline.)
>
> os.popen has been replaced by the subprocess module, so I suppose the
> new preferred method is:
>
> from subprocess import Popen, PIPE
> hostinfo = Popen(["uname", "-srvi"], stdout=PIPE).communicate()[0].strip()
>
>
> Looks ugly to me, but there we are.

The easy way to fix things that look ugly but are the right thing to do is to 
wrap them up into a utility function and call the utility function everywhere.

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco