Re: Hurd and Unix/Linux and Plan9 features

[Shams]

Does this mean that something like "cd .." or "ls .." will no work in 
ngHurd?

Is the primary reason for not supporting hardlinks due to the fact
that the programmer has to decide whether doing a cd .. from inside
a hard linked directory will move up to the parent directory of where
the hard link resides or should it be the parent of the actual target?

Thanks
Shams

-- 

<olafBuddenhagen@gmx.net> wrote in message 
news:20070203161803.GB246@alien.local...
> Hi,
>
> On Sat, Feb 03, 2007 at 12:49:57PM +0700, Ivan Shmakov wrote:
>> >>>>>"S" == Shams  <shams@orcon.net.nz> writes:
>
>> S> * Also will it support hard links for directories?
>>
>>        This problem was discussed on the list some time ago.  My
>>        opinion that it /shouldn't/ be done.  If one thinks of a
>>        directory as a mapping of file names to actual file objects,
>>        and of hard links as the alternate names to a file (directory)
>>        object, then it becomes hard to decide, which file (directory)
>>        the `..' name is mapped to?
>
> Well, as you seem to have followed the ngHurd discussions, you should be
> aware that this has shown to be only one of the reasons why having ".."
> links in the filesystem is a bad idea. ngHurd almost certainly won't
> have these, and in fact it might be changed in the existing
> implementation as well. So, this is not really a reason to avoid
> hardlinks to directories.
>
> In another discussion at a different place, someone pointed out that
> hardlinked directories are problematic, because this way loops are
> possible, and the filesystem would no longer be a directed graph. No
> idea whether this is a serious problem in practice.
>
>> S> 2. Will it support the Linux LVM concept?
>>
>>        Looks like with HurdNG's ``space banks'', things would be even
>>        better than with the Linux LVM.
>
> I think the space bank concept is rather orthogonal to partitions and
> LVM. Space banks are about allocating memory from the available stores,
> not about how stores are laid out on HD.
>
> -antrik-