[Tutor] How does this work?

Tony Cappellini cappy2112 at gmail.com
Wed Feb 7 18:25:32 CET 2007

> If I understand you, you have a python cmdline app that does something
> useful. You have users who aren't comfortable with the command line, so
> you are writing a GUI wrapper that calls the cmdline app with popen().
That is correct

> A better approach is to turn the functional part of the cmdline app -
> the code that does the real work - into an importable module.
it already is importable

>>Then your GUI app can import and use this module directly, instead
of doing hacks
> with popen() and stdout.

This all worked fine, until the author of the cmd line app stopped
using stdout and started using the logging module. Now I cannot
capture any output from his module.

> You don't even need a separate module for the cmdline app if it is
> written correctly - the command-line-specific part can be in an main()
> function that is only called if the module is run as main.

not totally true. It must be a stand-alone app, because there are
people using it now and many don't want to use the gui.
It is maintained completely independent of the gui by people other
than myself.. Any changes in the cmdline app should not affect the
gui. That was the intent by the author anyway. The use of the logging
module happens to be an exception to this.

Using popen() in a thread was a nice clean way to capture it's output.
Perhaps the exec/eval isn't so clean it's just what first came to mind.

I've already switched the exec/eval code to the import style.

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