bug#865: 23.0.60; The directory is unsafe today

[Lennart Borgman (gmail)]

Jason Rumney wrote:
> Lennart Borgman (gmail) wrote:
>>   drwxrwxrwx  1 Administrators Domain Users 0 03-07 11:14 server
>>
>> The part that where server-unsure-safe-dir barks is
>>
>>   (eql (nth 2 attrs) (user-uid))
>>
>> This check is maybe something that should be skipped on w32? As you can
>> see from the dired output above it will get "Domain Users" in my case.
>>   
> 
> I think it will get "Administrators" in fact, but it is still wrong.
> This is caused by a misfeature of Windows, that if the creator of a file
> is a member of the local "Administrators" group, then ownership is
> assigned to "Administrators" instead of the individual user. I think a
> similar problem will occur on FAT32 systems where ownership is assigned
> to "Everyone".
> 
> Eli, is it possible to tell the difference between an individual user
> and a group when we get the owner from the system? If so, we could check
> if the current user is a member of that group, and if so report them as
> the owner rather than the whole group, to work around ownership tests
> like this in lisp code.

I can see what you want to achieve, but why not just check with
file-writeable-p here? Is not that more correct?