Re: [matplotlib-devel] Another try at interactive gui thread

[Fernando P. <Fer...@co...>]

Steve Chaplin wrote:

> To run a background process as a thread you would need to redirect its
> stdout somewhere (StringIO for example). The problem with using threads
> for this is that they share the stdout with the main thread, so if you
> redirect the background threads stdout you will redirect the python
> interpreters stdout too!
> You could run a background process as an actual process and not a thread
> (and Python 2.4 has a new subprocess module which unifies the previous
> solutions of os.system, os.spawn*, os.popen*, popen2.*, commands.*). It
> lets you redirect stdout, but is used for running executables, not
> calling python functions.
> 
> It has me stumped too, how can you call a python function and redirect
> its stdout independent of the python interpreters stdout?

Not as far as I know.  That's why I think the only solution for the whole 
'backgrounding' problem with stdout is to put everything into a gui window (a 
la mathematica notebooks).  I've been thinking about it, and the proper way to 
write it is probably with _two_ python processes.  One would be the gui 
environment, and the other would be just a 'kernel' executing commands.  The 
stdout of the kernel would then be connected to an object capable of putting 
the results of each command next to the input cell which generated them.  I 
bet that's pretty much how Mathematica is organized, simply because it looks 
like the only reasonable way to deal with the issue.

Cheers,

f