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[nfsv4] Re: rfc8881bis: Symlink support on Windows-based servers and NTFS

Martin Wege <martin.l.wege@gmail.com> Sun, 25 January 2026 21:44 UTC

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From: Martin Wege <martin.l.wege@gmail.com>
Date: Sun, 25 Jan 2026 22:43:56 +0100
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Subject: [nfsv4] Re: rfc8881bis: Symlink support on Windows-based servers and NTFS
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On Sun, Jan 25, 2026 at 10:39 PM Nico Williams <nico@cryptonector.com> wrote:
>
> On Sun, Jan 25, 2026 at 01:17:47PM -0800, Rick Macklem wrote:
> >      (I don't think anyone would expect a symlink created by a
> >       POSIX-like system to work for Windows or vice versa.)
>
> Relative symlink targets, after / <-> \ substitution should work just
> find on both.
>
> UNCs could get mapped to /net-style paths.

No, UNCs are mapped to double-slash paths. That's where UWIN and
CYGWIN got their inspiration from.
Example: \\nfsserver1234\share1\ becomes //nfsserver1234/share1/

CYGWIN, UWIN, SFU all support this, and so do the Windows NFSv4 drivers.

>
> All other absolute symlink targets really can't be mapped.  One could
> try to map drive-letter paths on POSIX like Cygwin does, say, but
> really, no.

Actually the Windows drivers do exactly that. The prefix is
configurable, for example CYGWIN uses /cygdrive/c/path1/,
MSYS2+SFU+UWIN uses /c/path1/

Thanks,
Martin

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