Writing traceback of an exception into a log-file

[Gabriel Genellina]

En Mon, 26 May 2008 05:31:27 -0300, <Dominique.Holzwarth at ch.delarue.com> escribió:

> I'm trying to write the traceback stack of an exception that is thrown into a log file, but currently all that's written is simply a "None" :-/
>
> Here's some example code of what I'm doing:
>
> Import traceback
> class myException(Exception):
>         def __init__(self):
>                 f = open('filename.txt', 'a')
>                 traceback.print_exc(file=f)
>                 f.close()
>
> The file handling (opening etc) works ok (I'm using the same file in combination with a Logger() object too) but the string written to the file is effectively just a "None".
>
> Could anyone explain to me how to properly use the traceback module with it's countless of functions? =)

Don't inherit from Exception - you should be able to log *any* exception, not only this specific one, I presume? print_exc writes "the exception currently being handled", not the one you're creating right now. Put the code above into your exception handler:

try:
     1/0
except:
     f = open('filename.txt', 'a')
     traceback.print_exc(file=f)
     f.close()

(or define a function and call it from the exception handler)

-- 
Gabriel Genellina