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Date: Wed, 5 Jan 2022 11:07:11 +0100
From: Corinna Vinschen <corinna-cygwin AT cygwin DOT com>
To: cygwin AT cygwin DOT com
Subject: Re: Support for ADS (Alternate Data Streams)
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On Jan  3 22:40, NightStrike wrote:
> On Sun, Jan 2, 2022, 15:51 <cygwin AT kosowsky DOT org> wrote:
> 
> > While I recognize that ADS is not supported by POSIX, I was wondering
> > what if any support for ADS might exist within Cygwin.
> >
> > The last time I looked into this was probably more than a decade ago
> > but I am seeing (unfortunately) more usage of ADS in the Windows
> > world, so I was wondering if there has been any effort to support in
> > Cygwin?
> >
> > --
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> 
> 
> FWIW, ntfs-3g under Linux maps these to extended attributes

Using the EA API as ntfs-3g with the streams_interface=xattr option
seems like a nice way to allow reading and writing ADS on Cygwin as
well.

Do you know how ntfs-3g performs the mapping?  For instance, I guess
that ADS are stored in the user.* namespace?  Does listxattr list ADS or
does it skip them?  Stuff like that.


Corinna

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