On Oct 8 12:16, Jonathan Lennox wrote: > Hi, following up on this issue from last year. The message I'm replying to > is at <https://cygwin.com/ml/cygwin/2014-04/msg00524.html>. > > The problem is weird behavior in Parallels Desktop-hosted Windows VMs, when > accessing the host's native Mac OS X filesystem. See the thread for the > details. > > On Wednesday, April 23 2014, "Corinna Vinschen" wrote to "cygwin@cygwin.com" > saying: > > > > At this point this is looking pretty clearly like a Parallels Tools bug. > > > I'll report it to them. > > > > Yes, that sounds good. Given that, I'm wondering if we should try to > > workaround this problem at all or rather wait to see if the vendor will > > fix the issue. > > No such luck, despite two major version revisions of Parallels Desktop (I'm > now on version 11.0.2) and moving to Windows 10 as the guest OS -- the bug > perists, unchanged. So it looks like Cygwin will need to add a workaround > for this filesystem to fix the problem.
Ok, we could do that. Can you compile and run the testcase from https://cygwin.com/ml/cygwin/2014-04/msg00523.html again? Does it still show 0 vs. 12 bytes? Dumb extra test: Does the output change if you reorder the calls, requesting FileStandardInformation first, FileNetworkOpenInformation second? > The output of /usr/lib/csih/getVolInfo seems to be unchanged from the output > I reported last year. > > > Thanks. This looks pretty much like a filesystem pretending to be > > FAT-like. There may be another problem lurking, which is, are the inode > > numbers (called "FileId" or "IndexNumber" in Windows) persistant? With > > FAT this is not the case, and given the above, it might be a problem... > > > > ...or not. I just realize that Cygwin doesn't even try to use the > > FileId as inode number on filesystems with FILE_PERSISTENT_ACLS==FALSE > > so, never mind. > > > > OTOH, does it support hardlinks? If so, two hardlinks to the > > same file would have different inode numbers on Cygwin. > > How would I figure these points out? Just create a hardlink on that drive using native means: $ touch foo $ cmd /c mklink /h bar foo Error at this point? No hardlinks. Otherwise: $ ls -li foo bar Are the inode numbers identical? Congrats, hardlinks work. But given the general FAT-iness of the getVolInfo output, I guess it doesn't maintain hardlinks. Corinna -- Corinna Vinschen Please, send mails regarding Cygwin to Cygwin Maintainer cygwin AT cygwin DOT com Red Hat
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