Running long script in the background

[Gabriel Genellina]

En Tue, 06 Feb 2007 16:44:52 -0300, wattersmt at gmail.com  
<wattersmt at gmail.com> escribió:

> On Feb 6, 2:02 pm, Dennis Lee Bieber <wlfr... at ix.netcom.com> wrote:
>> On 6 Feb 2007 07:37:33 -0800, "watter... at gmail.com"
>> <watter... at gmail.com> declaimed the following in comp.lang.python:
>>
>> > Everything works fine until I call the popen function, then it
>> > freezes.  What I want is to print the output in real time, just like
>> > it does when I run it from a shell.
>>
>>         And you want /this/ in a web page?
>>
>>         I don't think HTTP is designed for that... As I understand it,  
>> it
>> expects to get a complete page back and then the transaction is complete
>> and forgotten (except for the presence of session cookies). To report

If the response does not include a Content-Length header, and has a  
Transfer-Encoding: chunked header, then it is sent in chunks (blocks) and  
the client is able to process it piece by piece.
See the server docs on how to enable and generate a chunked response. On  
Zope 2, by example, it's enough to use response.write().

> Web pages can show output as it's sent.  For testing I created a
> script on the server that untars a 600 meg volume, I can see each file
> name show up in my browser instantly, just like it should.  The other
> script I'm trying to run won't show anything until the entire process
> is complete and it's just a bunch of echo statements in a for loop,
> I'm not sure why they behave differently.

Are you sure the other process is executing? and not buffered? and you're  
reading its output line by line?

-- 
Gabriel Genellina