[Libguestfs] want to access the page file of VM from host on Xen platform using libguestfs

[Richard W.M. Jones]

On Thu, Feb 09, 2012 at 03:17:22PM -0800, Irfan Ahmed wrote:
> I am using Xen and want to access the page file contents of  windows
> XP SP2 virtual machine from dom0. Is it possible to read the page
> file of live Windows XP virtual machine using libguestfs. I have a C
> program and want to extend its functionality using
> libguestfs. Please help me how this can be done.

Yes; this can be done by reading the file through libguestfs, which is
what 'virt-cat' (a C program) does.

I would suggest you start with these two examples:

http://libguestfs.org/guestfs-examples.3.html
https://github.com/libguestfs/libguestfs/blob/6ca8a2db6d6f1028a35ece616af44538074483fc/cat/virt-cat.c#L273

If you need to locate the page file (ie. it's not in a default
location) then you will have to read that from the registry, which
libguestfs can also do.

If the guest is live you won't simply be able to keep a handle open
and re-read the file.  You might need to map the file to disk blocks
and read them directly.  (This is a bit more experimental)

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
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