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Date: Mon, 16 Nov 2009 13:31:38 +0100
From: Thomas Wolff <towo AT towo DOT net>
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Subject: Re: Seems like treatment of NTFS ADS (foo:bar) changed between 1.5     	and 1.7 but not mentioned in What's Changed
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Corinna Vinschen wrote:
> On Nov 16 12:56, Thomas Wolff wrote:
>   
>> Andy Koppe wrote:
>>     
>>> I'd suspect the support for ADSs in 1.5 was rather accidental anyway.
>>> POSIX programs certainly don't know about them, and you get the rather
>>> weird situation that "files" like foo:bar can be accessed but don't
>>> show up in the directory they're in. Hence I think the right way to
>>> access ADSs is via Windows tools. Unless there is a POSIXy way to
>>> represent them?
>>>       
>> I've only learned about this ADS stuff recently but yes, I think,
>> simply using the "a:b" syntax (which is also used by Windows tools)
>> and handling them as a virtual file is a quite obvious POSIX way to
>> do it.
>> So if it worked in 1.5, whether accidental or not, I think it should
>> continue to work in 1.7.
>>     
>
> It's a deliberate change.  It's more important to support as much POSIXy
> filenames as possible than to access streams.  I agree with Andy.  Use
> Windows tools to use them.
>   
But with it being supported, "foo:bar" *is* a POSIX filename and can 
quite transparently be handled like a file, just that the underlying 
filesystem in some cases (i.e. if it is NTFS) maps it to a fork of some 
other file. So in practice, it *is* actually a file too, despite the 
fact that MS uses weird terminology and inconsistent tooling for it.
And since I read that the use cases for ADS may increase with future 
Windows versions, I just thought it should be a good idea not to ignore 
these files.
Moreover, this transparent mapping would also solve the copy/backup 
problem discussed in the other thread (was it "rsync"?) and actually all 
problems at once, like including these things in zip archives etc.

Thomas

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