Re: determine if os.system() is done

Xah Lee wrote: 
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.

 Xah
 xah@xxxxxxxxxx
∑ http://xahlee.org/


As far as I can tell from the docs (worth reading), system(command) doesn't return until the process has completed. It would have to do some fancy footwork to return the exit code BEFORE the process had completed!

Steve
.

Relevant Pages

  • Re: determine if os.system() is done
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  • Re: determine if os.system() is done
    ... Xah Lee wrote: ... thiss.gz && tail thiss"), but i wish to know if there's non-hack way to determine when a system process is done. ...
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