Re: BFFS 1.5

[Stefan Hensen <hensen%wpos4.physik.uni-wuppertal.de@localhost>]

On 18 Aug 1998, Georges Heinesch wrote:

> Did you notice that selection (checked gadget) of ...
> 
>  1 = Turn on automatic symlink resolution
>  2 = Turn on case independence.  If you are familiar with the
>      Amiga filesystem, you probably want to turn this on.
>  4 = Make filesystem respect UNIX paths and not AmigaDOS paths
> 
> ... in BBFSTool on, results in a PreAlloc value of 0. This is in
> contradiction with the doc/user_manual.
> 
> I tested it and a PreAlloc Value of 0 (with mounting as DOSDriver or
> through the RDB) really means that the access to files is case
> dependant [2]. This would mean that the doc/user_manual is correct,
> and BFFSTool shows wrong figures. I confirmed this by setting PreAloc
> of the BSDROOT: to 0 and the BSDUSR: to 7. BFFSTool showed the
> opposite!
> 
> The first option (automatic symlink resolution) behaves opposite of
> what is expected. "0" switches it *ON*, "1" *OFF*!

It seems indeed that these three bits are somehow inverted in the value
displayed as PreAlloc in BFFSTool. If they are set in the mountlist or the
RDB, the options appear as selected (checked gadgets) but the displayed
PreAlloc value is 0. The reason for this seems to be unclear. However, the
other bits seem to work as expected.

> Looking at the third option (respect UNIX paths), does this incluence
> something else than the 'cd /' command (goes to / [UNIX] or one
> directory up [AmigaOS])?

So far, I have not noticed other differences apart from the meaning of /.

> > I find it useful to set also 'invert the definition of the
> > other/group permission bits' (32), because otherwise one gets
> > settings like
> > '-rw--wx-wx' instead of '-rw-r--r--' and '-rwx-w--w-' instead of
> > '-rwxr-xr-x' when copying files from one side to the other.
> 
> Why is this not done immediately?
> It is logical that '-rw-r--r--' should be used instead of
> '-rw--wx-wx'. Anyway, it's not explained how the group/other
> permissions are mapped to the UNIX side when copying from AmigaOS to
> UNIX. Are the group/other permissions always 'r--' when this flag is
> set and '-wx' when it's unset?

When copying from AmigaOS to Unix, the group/other permissions of the
destination file on the Unix partition depend on those of the source file
on the AmigaOS partition. You usually do not see the group/other
permissions on AmigaOS partitions unless you use things like
MultiUserFilesystem or the file utilities from GeekGadgets/ADE, but they
exist in principle. Unfortunately, it is not completely clear to me how
they are mapped by BFFS. Some combinations of permission bits look
reasonable after copying, but some look quite strange. Furthermore, it
seems that the above mentioned option has only an influence on reading from
BSD partitions, but not on writing to them.
Perhaps this is one of the reasons why BFFS is still called 'beta' ...

> 64 = Report space free relative to minfree (instead of actual)
> 
> C:Info showed indeed some differences (52% full or 57% full). But what
> is the difference between both settings?

On BSD filesystems, the space available to users is usually slightly
smaller than the real physical size for performance reasons (see newfs(8)
and tunefs(8), option '-m'). NetBSD's df command displays the free space
available to users. C:Info usually displays the total free space relative
to the physical size. If the above mentioned option is set, C:Info should
display only the free space available to users. However, the reported
values still seem to differ from those displayed by NetBSD's df command.

Regards,

Stefan Hensen

----------------------------------------------------------
Stefan Hensen
e-mail: hensen%wpos4.physik.uni-wuppertal.de@localhost