On 05/21/2010 08:11 AM, Guido Winkelmann wrote: > Hi, > > Sometimes when stopping a virtual domain using virDomainDestroy(), I come > across a domain that is already stopped. (For example when someone already > stopped the domain manually using virsh or because the guest OS issued a > shutdown.) This is a special case that I absolutely need to catch and handle. > In virt-manager, we basically do: def destroy(vm): if vm.is_running(): vm.destroy() return I'd recommend doing something similar in your app: no reason to run a command if you can check ahead of time if it will fail. You can use virDomainIsActive to check the domain status. > Unfortunately, when this happens, and I call virGetLastError() afterwards, I > always just get the error code VIR_ERR_OPERATION_INVALID, which doesn't look > very precise to me... > > Two questions about this: > > Is the domain not running at that moment the only possible condition that can > trigger this particular error code when calling virDomainDestroy()? > Yes, there are other errors but none that use OPERATION_INVALID. > Can't we have a more obvious/precise error code in that case, like > VIR_ERR_DOMAIN_NOT_RUNNING or something like that? > Sounds like a reasonable idea, won't help you though if your app needs to support older versions.

Hi, Sometimes when stopping a virtual domain using virDomainDestroy(), I come across a domain that is already stopped. (For example when someone already stopped the domain manually using virsh or because the guest OS issued a shutdown.) This is a special case that I absolutely need to catch and handle. Unfortunately, when this happens, and I call virGetLastError() afterwards, I always just get the error code VIR_ERR_OPERATION_INVALID, which doesn't look very precise to me... Two questions about this: Is the domain not running at that moment the only possible condition that can trigger this particular error code when calling virDomainDestroy()?

Can't we have a more obvious/precise error code in that case, like VIR_ERR_DOMAIN_NOT_RUNNING or something like that?

On 5/24/2010 6:24 AM, Daniel P. Berrange wrote: >On Fri, May 21, 2010 at 02:11:47PM +0200, Guido Winkelmann wrote: > >>Hi, >> >>Sometimes when stopping a virtual domain using virDomainDestroy(), I come >>across a domain that is already stopped. (For example when someone already >>stopped the domain manually using virsh or because the guest OS issued a >>shutdown.) This is a special case that I absolutely need to catch and >>handle. >> >>Unfortunately, when this happens, and I call virGetLastError() >>afterwards, I >>always just get the error code VIR_ERR_OPERATION_INVALID, which doesn't >>look >>very precise to me... >> >>Two questions about this: >> >>Is the domain not running at that moment the only possible condition that >>can >>trigger this particular error code when calling virDomainDestroy()? >> >The VIR_ERR_OPERATION_INVALID is a precise code that says the request >operation is not valid wrt the current state of the guest. So for the >virDomainDestroy() method, the only cause of this message is requesting >destroy of a guest that is not running. > You are saying there is, and can only ever be, one possible way that the operation could ever be considered invalid?

Even within the limited scope of virDomainDestroy() and the particular values it was called with, I find that hard to believe on general principle.