bufsize in subprocess

[yves at zioup.com]

Is this the expected behaviour?
When I run this script, it reads only once, but I expected once per line with 
bufsize=1.

What I am trying to do is display the output of a slow process in a tkinter 
window as it runs. Right now, the process runs to completion, then display the 
result.

     import subprocess

     com = ['/bin/ls', '-l', '/usr/bin']
     with subprocess.Popen(com, bufsize=1, stdout=subprocess.PIPE, 
stderr=subprocess.STDOUT) as proc:
         print('out: ' + str(proc.stdout.read(), 'utf8'))


Thanks.

-- 
Yves.                                                  http://www.SollerS.ca/
                                                        http://ipv6.SollerS.ca
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