determine if os.system() is done

[Jeremy Jones]

Thomas Bellman wrote:

>"Xah Lee" <xah at xahlee.org> writes:
>
>  
>
>>suppose i'm calling two system processes, one to unzip, and one to
>>tail to get the last line. How can i determine when the first
>>process is done?
>>    
>>
>
>  
>
>>Example:
>>    
>>
>
>  
>
>>subprocess.Popen([r"/sw/bin/gzip","-d","access_log.4.gz"]);
>>    
>>
>
>  
>
>>last_line=subprocess.Popen([r"/usr/bin/tail","-n 1","access_log.4"],
>>stdout=subprocess.PIPE).communicate()[0]
>>    
>>
>
>  
>
>>of course, i can try workarounds something like os.system("gzip -d
>>thiss.gz && tail thiss"), but i wish to know if there's non-hack way to
>>determine when a system process is done.
>>    
>>
>
>Have you tried reading the manual for the subprocess module?  You
>just *might* find the answer to your question if you look at what
>you can do with Popen objects.
>
Oh, come on.  Don't you know that all Python documentation is rubbish 
and not worth reading, written by IT idiots who throw around useless 
jargon and indulge in extreme forms of self-gratification?  Someone of 
the caliber of Xah Lee would *never* stoop so low as to actually read 
the documentation.  It is beneath him.  Instead, he posts messages to a 
group of IT idiots who throw around useless jargon and indulge in 
extreme forms of self-gratification in posting answers to questions.

<snip>

JMJ