Re: [libvirt] [PATCH 2/9] Define the internal driver API for vol wiping

On 03/15/2010 08:13 PM, David Allan wrote: Any reason this was introduced in the middle of the struct, rather than at the end? Sticking stuff in the middle tends to be asking for off-by-one shifts of all the remaining elements in the struct, especially if you ever mix objects compiled across the time when the element was added. Whereas always sticking new entries at the end allows you to maintain a measure of back-compatibility, where an older object still fits in the first half of the struct, and given enough version/sizing information, a newer server can correctly assume that struct members beyond a given offset are effectively null when talking to a client that was compiled against the older struct definition. On the other hand, you probably aren't the first to make a modification like this, so this is more an issue of me asking about the code to learn about it than it is a request for you to make a change. -- Eric Blake eblake(a)redhat.com +1-801-349-2682 Libvirt virtualization library http://libvirt.org