os.path and Windows UNC paths

[Trent Mick]

[Tim Howarth wrote]
> I've been trying to use os.path.exists and  os.path.isdir on
> Windows(2000) UNC paths with Python 2.2 but it doesn't seem to behanve
> sensibly.
> 

There is a bug for this already:
    http://python.org/sf/513572


I tend to use this function:

def _isdir(dirname):
    """os.path.isdir() doesn't work for UNC mount points. Fake it.
    
    # For an existing mount point (want: _isdir() == 1)
    os.path.ismount(r"\\crimper\apps") -> 1
    os.path.exists(r"\\crimper\apps") -> 0
    os.path.isdir(r"\\crimper\apps") -> 0
    os.listdir(r"\\crimper\apps") -> [...contents...]
    # For a non-existant mount point (want: _isdir() == 0)
    os.path.ismount(r"\\crimper\foo") -> 1
    os.path.exists(r"\\crimper\foo") -> 0
    os.path.isdir(r"\\crimper\foo") -> 0
    os.listdir(r"\\crimper\foo") -> WindowsError
    # For an existing dir under a mount point (want: _isdir() == 1)
    os.path.mount(r"\\crimper\apps\Komodo") -> 0
    os.path.exists(r"\\crimper\apps\Komodo") -> 1
    os.path.isdir(r"\\crimper\apps\Komodo") -> 1
    os.listdir(r"\\crimper\apps\Komodo") -> [...contents...]
    # For a non-existant dir/file under a mount point (want: _isdir() ==
    # 0)
    os.path.ismount(r"\\crimper\apps\foo") -> 0
    os.path.exists(r"\\crimper\apps\foo") -> 0
    os.path.isdir(r"\\crimper\apps\foo") -> 0
    os.listdir(r"\\crimper\apps\foo") -> []  # as if empty contents
    # For an existing file under a mount point (want: _isdir() == 0)
    os.path.ismount(r"\\crimper\apps\Komodo\latest.komodo-devel.txt") -> 0
    os.path.exists(r"\\crimper\apps\Komodo\latest.komodo-devel.txt") -> 1
    os.path.isdir(r"\\crimper\apps\Komodo\latest.komodo-devel.txt") -> 0
    os.listdir(r"\\crimper\apps\Komodo\latest.komodo-devel.txt") -> WindowsError
    """
    if sys.platform[:3] == 'win' and dirname[:2] == r'\\':
        if os.path.exists(dirname):
            return os.path.isdir(dirname)
        try:
            os.listdir(dirname)
        except WindowsError:
            return 0
        else:
            return os.path.ismount(dirname)
    else:
        return os.path.isdir(dirname)



-- 
Trent Mick
TrentM at ActiveState.com