Ian Simcock wrote:
> Greetings all.
>
> I'm using Python 2.7 under Windows and am trying to run a command line
> program and process the programs output as it is running. A number of
> web searches have indicated that the following code would work.
>
> import subprocess
>
> p = subprocess.Popen("D:\Python\Python27\Scripts\pip.exe list -o",
> stdout=subprocess.PIPE,
> stderr=subprocess.STDOUT,
> bufsize=1,
> universal_newlines=True,
> shell=False)
> for line in p.stdout:
> print line
>
> When I use this code I can see that the Popen works, any code between
> the Popen and the for will run straight away, but as soon as it gets to
> the for and tries to read p.stdout the code blocks until the command
> line program completes, then all of the lines are returned.
>
> Does anyone know how to get the results of the program without it
> blocking?
The following works on my linux system:
import subprocess
p = subprocess.Popen(
["ping", "google.com"],
stdout=subprocess.PIPE)
instream = iter(p.stdout.readline, "")
for line in instream:
print line.rstrip()
I don't have Windows available to test, but if it works there, too, the
problem is the internal buffer used by Python's implementation of file
iteration rather than the OS.
--
http://mail.python.org/mailman/listinfo/python-list
