[PLUGIN] bzr uncommit updated

[John Yates]

Aaron,

I do believe that if you reread the referenced
article closely you will see that there is very
little discussion of hard links and that all the
nasty behavior centers around Windows' equivalent
of symbolic links.  Little surprise there given
the chaos that occasioned the NTFS5 introduction
of the junction or reparse point.  They became a
veritable "Swiss Army Knife" used support mounting
of non-root file systems, simple redirection and
extensible semantics (a bit like Reiser4 plug-ins).

Hardlinks OTOH have been in NTFS since day one.
They were included specifically to support Posix
semantics.

I encourage you to enable them on Windows as an
experiment.  So long as the underlying file system
is NTFS (though sadly not NTFS over CIFS/SMB) you
should be happily surprised.

/john

-----Original Message-----
From: Aaron Bentley [mailto:aaron.bentley at utoronto.ca]
Sent: Monday, September 26, 2005 2:15 PM
To: John Yates
Cc: John A Meinel; Bazaar-NG
Subject: Re: [PLUGIN] bzr uncommit updated


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John Yates wrote:
> If you test only for the platform then in a Windows
> environment you must conservatively eschew hardlinking.
> If OTOH you test for the filesystem hosting the bzr
> workspace, and if we assume that the vast majority of
> Windows boxes likely to run bzr will be W2K or later
> and will be NTFS-based, then you can exploit hardlinks.

NTFS supports both hard links and symbolic links, but most Windows
programs are unaware of them, and this can lead to problems.  For
example, Explorer exhibits bizarre behaviour when symlinks are deleted:

http://shell-shocked.org/article.php?id=284

So I think that it's risky to support hard links on Windows.

> To whit, Mercurial's WhatsNew:

Yes, I'd seen that.  Clearly, they're braver than I.

Aaron
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