[Python-Dev] The path module PEP (original) (raw)

Stefan Rank stefan.rank at ofai.at
Thu Jan 26 15:47:05 CET 2006

on 26.01.2006 14:15 Paul Moore said the following: [snip]

Also note that my example Path("C:", "Windows", "System32") above is an absolute path on Windows. But a relative (albeit stupidly-named :-)) path on Unix. How would that be handled?

wrong, Path("C:", "Windows", "System32") is a relative path on windows. see below.

Not that os.path gets it perfect:

Python 2.4 (#60, Nov 30 2004, 11:49:19) [MSC v.1310 32 bit (Intel)] on win32 Type "help", "copyright", "credits" or "license" for more information.

import os os.path.join("C:", "Windows", "System32") 'C:Windows\System32' os.path.join(".", os.path.join("C:", "Windows", "System32")) '.\C:Windows\System32'

this is misleading. observe::

In [1]: import os

In [2]: os.path.join(".", os.path.join("C:", "Windows", "System32")) Out[2]: '.\C:Windows\System32'

but::

In [3]: os.path.join(".", os.path.join("C:\", "Windows", "System32")) Out[3]: 'C:\Windows\System32'

The second example uses an absolute path as second argument, and as os.path.join should do, the first argument is discarded.

The first case is arguably a bug, since, on windows, C:Windows\System32 is a path relative to the current directory on disk C: If the cwd on C: would be C:\temp then C:Windows\System32 would point to C:\temp\Windows\System32

The problem is that Windows has a cwd per partition... (I cannot even guess why ;-)

For the sake of illustration, the following is a WinXP cmd session::

Microsoft Windows XP [Version 5.1.2600] (C) Copyright 1985-2001 Microsoft Corp.

C:\temp>d:

D:>cd HOME

D:\HOME>c:

C:\temp>d:

D:\HOME>c:

C:\temp>cd d:bin

C:\temp>d:

D:\HOME\bin>

[snip]

Arguably, Path objects should always maintain an absolute path - there should be no such thing as a relative Path. So you would have

you realise that one might need and/or want to represent a relative path?

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