[Discuss] odd file permissions problem with cygwin, windows XP, and matlab

[Adam Parkin]

pw wrote:
> Incidentally, my XP user account has administrative permissions
> so I can't understand where matlab has a problem with any file.
> Not that I'd want to but I should be able to load my pagefile.sys
> into matlab and it shouldn't care, nor should XP.

This won't be particularly helpful, but pagefile.sys can't be opened by 
any program while Windows is running as the file is repeatedly being 
written to by the OS.

> Anyway, I'm wondering if anyone has run into any related types
> of file/directory permissions problems with cygwin or matlab
> on XP.

I have, although not quite like you describe.  I've found that sometimes 
Cygwin gets confused about who the owner of a file is on a NTFS-based 
filesystem.  For example, I once moved some files around on a 
Windows-based machine using Windows Explorer, and then in Cygwin a "ls 
-Fl" showed the owner as "????????" IIRC.  I ended up having to do chown 
and chmod on the files manually to fix.

I think a big part of the problem is that there is no native concept of 
Unix like permissions (UGO and RWX) in NTFS, so there is always some 
trickery/hackery involved in getting programs that expect Unix-like 
permissions to work correctly in Cygwin.  Then again, I'm not hugely 
familiar with the NTFS filesystem, so take all this with a good sized 
grain of salt.

At any rate, I have no idea why any of this would affect Matlab the way 
you describe.
-- 
--
Adam Parkin
E-mail: pzelnip at gmail.com
Blog: http://pzelnip.blogspot.com/
----------------------
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