Why does bufsize=1 not work in subprocess.Popen ?

I. Myself No.Spam at Spam.none
Sat Apr 29 19:05:23 EDT 2006


Marc 'BlackJack' Rintsch wrote:
> In <V6R4g.89900$P01.79112 at pd7tw3no>, I. Myself wrote:
>
>   
>> I read in the docs that "bufsize=1" causes line buffering.  (for 
>> subprocess.Popen)
>>
>> The following tiny program launches an executable file and then receives 
>> its output.  That works, but I want to
>> receive each line as it is ouput, not all of the lines at termination, 
>> which is what is happening.
>>     
>
> From the Python side you can only control Python's input buffer but not
> the output buffer of the external program you are starting.  I guess that
> programs buffers its output.
>
> Ciao,
> 	Marc 'BlackJack' Rintsch
>   
That makes sense.  I remember now that someone told me that Windows 
sends line-by-line only to the screen.  To a pipe it sends buffers full.

Thanks,

Mitchell Timin

-- 
I'm proud of http://ANNEvolve.sourceforge.net.  If you want to write software,
or articles, or do testing or research for ANNEvolve, let me know.

Humans may know that my email address is: (but remove the 3 digit number)
zenguy at shaw666 dot ca





More information about the Python-list mailing list