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Date:	Tue, 03 Nov 2009 01:49:39 -0500
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From:	"Jeffrey J. Kosowsky" <cygwin_at_kosowsky_dot_org AT useleftsideaddressgmail DOT org>
To:	cygwin AT cygwin DOT com
Subject:	Accessing GLOBALROOT paths - a potential compromise???
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I know that there have been multiple threads about the pros/cons of
being able to access XP/Vista style \\?\GLOBALROOT paths.

However, not being able to access them limits one's abilities to use
things like shadow copies since they create shadow devices that are only
accessible by such a path. For example
		   \\?\GLOBALROOT\Device\HarddiskVolumeShadowCopy1

The only hack that I have found to get around this is to use an *old*,
*unsupported* Microsoft routine called 'dosdev' which allows you to
assign drive letters to devices, including using the GLOBALROOT
format.

However, it has several disadvantages:
- It is old and not available
- It is unsupported
- It is mostly undocumented with different versions and command lines
  for different Windows OS's -- so it is not portable across Windows
  implementations (neither is vshadow.exe but that is another issue)
- It is not cygwin (and requires DOS type '/' parameters)
- It requires login access so it won't work with ssh login with
  username=SYSTEM

If the cygwin developers are worried about performance or bug issues
with adding the GLOBALROOT syntax to *all* file operations, how about
implementing one of the two below compromises:

1. Just allow the GLOBALROOT implementation for mount.
   This would allow you to mount the device using a drive letter and
   then access it that way (similar to dosdev.exe itself).

2. If you don't want to touch mount itself, then how about writing an
   alternative restrictive version of mount called something else that
   just handles the special case of assigning/mounting a drive letter
   to the GLOBALROOT device -- i.e. basically implementing the dosdev
   functionality in a cygwin way.

Alternatively, is there any other way (other than dosdev.exe to access
global root partitions)


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