From mboxrd@z Thu Jan  1 00:00:00 1970
From: Wei Liu <liuw@liuw.name>
Subject: Re: Event from dom0
Date: Thu, 18 Aug 2011 09:33:49 +0800
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On Wed, Aug 17, 2011 at 12:52 PM, Jinesh M.K <mkjinesh@gmail.com> wrote:
> Hi,
>
> How to capture a event(eg:file copying) from dom0?
>

Well, there is a technique called "system call intercepting".

File copying or any other kinds of operation need the help from the
kernel -- that is, they will issue syscalls. If you can intercept
syscall in Xen, then Xen can tell your little daemon in Dom0 what's
happening in DomU.

It is doable, because my colleage has done something similar before.
However, this kind of operation slows down the whole system, because
it requires virtual machine introspection to eliminate semantic gap
between Dom0 and DomU, and the frequent switching from Xen, Dom0 and
DomU is certainly a performance hit.

Or you can try Pasi's way, depending on your need.

Wei.