os.popen on windows: loosing stdout of child process

[Gabriel Genellina]

En Sat, 12 May 2007 00:46:16 -0300, Greg Ercolano <erco at 3dsite.com>  
escribió:

> 	When I use os.popen(cmd,'w'), I find that under windows, the stdout
> 	of the child process disappears, instead of appearing in the DOS window
> 	the script is invoked from. eg: [...]
> 	When I run the same python program on a unix box, the output
> 	from 'nslookup' appears in the terminal, as I'd expect.
>
> 	Shouldn't popen() be consistent in its handling of the child's
> 	stdout and stderr across platforms?
>
> 	Maybe I'm missing something, being somewhat new to python, but
> 	an old hand at unix and win32 and functions like popen(). Didn't
> 	see anything in the docs for popen(), and I googled around quite
> 	a bit on the web and groups for eg. 'python windows popen stdout lost'
> 	and found nothing useful.

Using the subprocess module is the recommended approach (as you can see on  
the os.popen documentation) and does what you want:

C:\TEMP>type foo2.py
import subprocess
p = subprocess.Popen("nslookup", stdin=subprocess.PIPE)
p.stdin.write("google.com\n")
p.stdin.close()

C:\TEMP>python foo2.py

C:\TEMP>Servidor predeterminado:  coyote.softlabbsas.com.ar
Address:  192.168.0.116

> Servidor:  coyote.softlabbsas.com.ar
Address:  192.168.0.116

Respuesta no autoritativa:
Nombre:  google.com
Addresses:  64.233.187.99, 64.233.167.99, 72.14.207.99

>
C:\TEMP>

For more info about subprocess usage, see  
http://docs.python.org/lib/module-subprocess.html

-- 
Gabriel Genellina