[Python-Dev] __file__ is not always an absolute path

[Christian Heimes]

Guido van Rossum schrieb:
> Are you sure you remember this right? The <code>.co_filename
> attributes will be unmarshalled straight from the bytecode file which
> indeed will have the relative path in this case (hopefully we'll
> finally fix this in 3.2 and 2.7). But if I read the code in import.c
> correctly, __file__ is set on the basis of the path of the file read,
> which in turn comes from sys.path which will have been "absolufied" by
> site.py. Or maybe this was so long ago that site.py didn't yet do
> that?

I ran into the problem years ago. I can recall the Python version but it
must have been 2.2 or 2.3, maybe 2.1. I'm not entirely sure how it
happened, too. All I can remember that I traced the cause down to the
way compileall was called. I've tried to reproduce the issue with Python
2.6 but failed. It looks like the code does the right thing.

Christian