[Python-Dev] [Python-3000] New proposition for Python3 bytes filename issue

[Guido van Rossum]

On Tue, Sep 30, 2008 at 12:42 PM, Terry Reedy <tjreedy at udel.edu> wrote:
> Guido van Rossum wrote:
>>
>> On Tue, Sep 30, 2008 at 11:13 AM, Georg Brandl <g.brandl at gmx.net> wrote:
>>>
>>> Victor Stinner schrieb:
>>>>
>>>> On Windows, we might reject bytes filenames for all file operations:
>>>> open(),
>>>> unlink(), os.path.join(), etc. (raise a TypeError or UnicodeError)
>>>
>>> Since I've seen no objections to this yet: please no. If we offer a
>>> "lower-level" bytes filename API, it should work for all platforms.
>>
>> I'm not sure either way. I've heard it claim that Windows filesystem
>> APIs use Unicode natively. Does Python 3.0 on Windows currently
>> support filenames expressed as bytes? Are they encoded first before
>> passing to the Unicode APIs? Using what encoding?
>
> In 3.0rc1, the listdir doc needs updating:
> "os.listdir(path)
> Return a list containing the names of the entries in the directory. The list
> is in arbitrary order. It does not include the special entries '.' and '..'
> even if they are present in the directory. Availability: Unix, Windows.
>
> On Windows NT/2k/XP and Unix, if path is a Unicode object, the result will
> be a list of Unicode objects."
>
> s/Unicode/bytes/ at least for Windows.
>
>>>> os.listdir(b'.')
> [b'countries.txt', b'multeetest.py', b't1.py', b't1.pyc', b't2.py', b'tem',
> b'temp.py', b'temp.pyc', b'temp2.py', b'temp3.py', b'temp4.py', b'test.py',
> b'z', b'z.txt']
>
> The bytes names do not work however:
>
>>>> t=open(b'tem')
> Traceback (most recent call last):
>  File "<pyshell#23>", line 1, in <module>
>    t=open(b'tem')
>  File "C:\Programs\Python30\lib\io.py", line 284, in __new__
>    return open(*args, **kwargs)
>  File "C:\Programs\Python30\lib\io.py", line 184, in open
>    raise TypeError("invalid file: %r" % file)
> TypeError: invalid file: b'tem'
>
> Is this what you were asking?

No, that's because bytes is missing from the explicit list of
allowable types in io.open. Victor has a one-line trivial patch for
this. Could you try this though?

>>> import _fileio
>>> _fileio._FileIO(b'tem')

-- 
--Guido van Rossum (home page: http://www.python.org/~guido/)