Re: [Bug-tar] tar and file meta data....

[Linda A. Walsh]

Tim Kientzle wrote:
> On Oct 31, 2011, at 6:04 PM, Linda A. Walsh wrote:
>   
> > [Tim]"zip" does exactly what you describe, and newer Info-Zip versions do a 
> > good job of preserving Unix permissions, timestamps, etc.
> >
> > Instantly, I think, but does it handle alternate data forks as exist on on 
> > Windows, Linux and Apple.?  Windows NTFS has 'extended data' or streams,
> > ACLs, and sensitivity/integrity label.  Linux has had them since the early
> > 90's when XFS came with them.  They've been added to other file systems since 
> > then.
> >
> > And Apple's file system also supports alternate data/resource forks.
> >     
>
> I'd be interested in an example showing a case where
> it's actually useful to transfer extended data between
> dissimilar systems.  Apart from ACLs (see below), I've
> yet to see any case where it was useful to do so.
>   
==== 

I didn't say you should untar a tarfile with alternate-system attributes
onto a system.

When I wrote that I was 99% thinking of linux where I was stuck with
xfsdump/restore for 10 years before rsync got them support a few years ago,
and cp finally got them ... well, recently, ...

I mean, it's not like it's the bleeding edge of tech...  AFAIK, the both
file Capabilities and ACL's on XFS are based on the extended attributes...
So if they'd just handle that, the rest would fall out.   Things may have
changed, but the extended attrs were the extra space where things like acls
and capabilities could live...

Now as for windows...somehow I doubt it would be that simple.   But linux --
please.

Then same-system to same-system.

As far as being general, put the extended attrs and acls save/restore into a
separate systems....hey....

 __It'd be nice__**  to have some xlation between windows and posix 1e,
though I know they don't map 1:1, samba, for example does an ok job of
mapping windows acls into XFS (Posix 1e) acls) and storing windows things
that don't fit into named attributes for later recall and use, or
cygwin<->win, or a system like rsync uses of storing anything unknown in a
extended-attr or blob...?

** -- future...



> Are MacOS data forks ever useful on Windows?
> Windows streams on Linux?
>   
----
   Yes...Windows streams are stored as EXTENDED attributes on a
Samba server, and reserved back as Windows attributes.   Being
able to backup restore from 1 environment to the other would be
very useful.


>   
> > star has (a multi tar format tar prog from the 90's has had
> > support for ACLS/extended attrs -- �
> >     
>
> Last I checked, Joerg only supported POSIX.1e ACLs with star.
>   
----
   Nep....supports extended attributes --for as long as he's supported 
ACL's...at least
in my exposure to it.


> Extending tar to work well with Windows would be a pretty complex undertaking.
> Windows has a very different set of file types, filename patterns, and 
> permissions
> than POSIX utilities such as 'tar'.
>   
====
   Yeah....
   Getting 'cp' to work musta been difficult....though it's only 
working over a linux and cygwin
layer at the moment...which would be 1000% better than what exists today 
in tar! ;-)

The rest...hey, I'm not asking for the world...(yet)....but getting it 
to work for linux/cygwin/
posix1e acls/extended attrs, would solve 60% of my problems 
w/tar...(since I don't have
a native 64-bit Win version now, it would be a bit of a stretch to ask 
for that AND one that
supports native win ACLS/ext-attrs(streams)...)...but that would a nice 
future goal...

But linux/cyg first?


Hope that clarifies and scopes a bit better..

I just mentioned all the platforms that now have native FS's that 
support such..
as a basis for needing tar upgraded to handle such...

Linda