Re: [libvirt] virConnectOpenReadOnly?
On Tue, Aug 26, 2008 at 03:45:06PM +0900, Jun Koi wrote:
According to the comment of virConnectOpenReadOnly, this function
has
some restrictions on available methods to control domains. Could you
be more specific? What kind of restrictions we are having (compare to
virConnectOpen())?
And when should we use virConnectOpenReadOnly() instead of virConnectOpen() ?
I don't think the list of restrictions is explicit anywhere, although
the idea of virConnectOpenReadOnly is to allow merely "safe" status/
monitoring-type operations, and not any operations which could change
the state of the system. Virt-top, for example, opens all connections
in read-only mode.
In ocaml-libvirt we actually enforce the restriction at compile time.
So at some point a very long time ago I went through the calls in
libvirt to see which ones are restricted. If you look at:
http://hg.et.redhat.com/virt/applications/ocaml-libvirt--devel/?f=6c6fec2...
then any calls which have the phantom type[1] of "[>`W] t" require
write access.
Rich.
[1] http://camltastic.blogspot.com/2008/05/phantom-types.html
--
Richard Jones, Emerging Technologies, Red Hat http://et.redhat.com/~rjones
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