DMARC-Filter: OpenDMARC Filter v1.4.2 delorie.com 514MdSih1600226
DMARC-Filter: OpenDMARC Filter v1.4.2 sourceware.org 38D8A3858D20
MIME-Version: 1.0
Date: Tue, 4 Feb 2025 23:37:52 +0100
Message-ID: <CAKAoaQ=c44QKPSN0=pweE+H=n2opxPnRjqVwcorow=y=_7TCHw@mail.gmail.com>
Subject: |IO_REPARSE_TAG_MOUNTPOINT| (Junctions) not working for remote
 filesystems in Cygwin ?
To: cygwin AT cygwin DOT com
From: Roland Mainz via Cygwin <cygwin AT cygwin DOT com>
Reply-To: gisburn AT nrubsig DOT org
Cc: Roland Mainz <roland DOT mainz AT nrubsig DOT org>
Content-Type: text/plain; charset="us-ascii"
Content-Transfer-Encoding: 7bit
Sender: "Cygwin" <cygwin-bounces~archive-cygwin=delorie DOT com AT cygwin DOT com>

Hi!

----

I am tinkering with Win32 reparse point (Junction) support and tried
to implement |IO_REPARSE_TAG_MOUNTPOINT| (and other reparse tags) in
our filesystems (mostly for automounter+NFSv4.1 referral support), but
it seems that Cygwin does not support |IO_REPARSE_TAG_MOUNTPOINT| for
"remote" filesystems:
---- snip ----
  2576        if ((rp->SymbolicLinkReparseBuffer.Flags &
SYMLINK_FLAG_RELATIVE) ||
  2577            check_reparse_point_string (psymbuf))
  2578          return PATH_SYMLINK | PATH_REP;
  2579      }
  2580    else if (!remote && rp->ReparseTag == IO_REPARSE_TAG_MOUNT_POINT)
  2581      {
  2582        /* Don't handle junctions on remote filesystems as
symlinks.  This type
  2583           of reparse point is handled transparently by the OS so that the
  2584           target of the junction is the remote directory it is
supposed to
  2585           point to.  If we handle it as symlink, it will be mistreated as
  2586           pointing to a dir on the local system. */
  2587        RtlInitCountedUnicodeString (psymbuf,
---- snip ----

The matching code in our filesystems seems to work in PowerShell and
cmd.exe - so what context am I missing ?

----

Bye,
Roland
-- 
  __ .  . __
 (o.\ \/ /.o) roland DOT mainz AT nrubsig DOT org
  \__\/\/__/  MPEG specialist, C&&JAVA&&Sun&&Unix programmer
  /O /==\ O\  TEL +49 641 3992797
 (;O/ \/ \O;)

-- 
Problem reports:      https://cygwin.com/problems.html
FAQ:                  https://cygwin.com/faq/
Documentation:        https://cygwin.com/docs.html
Unsubscribe info:     https://cygwin.com/ml/#unsubscribe-simple