[Python-Dev] Inconsistencies if locale and filesystem encodings are different

[Victor Stinner]

Le jeudi 07 octobre 2010 18:35:09, M.-A. Lemburg a écrit :
> Victor Stinner wrote:
> > Hi,
> > 
> > A PYTHONFSENCODING environment variable was added to Python 3.2: issue
> > #8622. This variable introduces an inconstency because the filesystem
> > and the locale encodings can now be different.
> > 
> > There are (at least) four issues related to this problem. We have 2
> > choices to
> > 
> > fix these issues:
> >  (a) use the same encoding to encode and decode values (it can be
> >  different
> > 
> > for each issue)
> > 
> >  (b) remove PYTHONFSENCODING variable and raise an error if locale and
> > 
> > filesystem encodings are different (ensure that both encodings are the
> > same)
> > 
> > Even if choice (a) is not easy to implement, it is feasible and I already
> > wrote some patches.
> > 
> > I don't understand how Python interact with other programs who ignore the
> > PYTHONFSENCODING environment variable. It's like Python uses its own
> > "locale".
> > 
> > Choice (b) looks easy to implement, but... there is the problem of Mac OS
> > X. Mac OS X uses utf-8 encoding for the filesystem (and not the locale
> > encoding), whereas it looks like the locale encoding is used for the
> > command line arguments. See issue #4388 for more information.
> > 
> > There is also maybe an useful usecase of the PYTHONFSENCODING, but I
> > don't remember which one :-)
> 
> You have to differentiate between the meaning of a file system
> encoding and the locale:
> 
> A file system encoding defines how the applications interact
> with the file system.
> 
> A locale defines how the user expects to interact with the
> application.

What is the encoding of the command line arguments? Locale or filesystem 
encoding? Is it different if an argument is a filename or a path?

-- 
Victor Stinner
http://www.haypocalc.com/