On 08/12/2010 03:00 AM, Soren Hansen wrote:
The current check for the size of the response from the uml monitor is problematic for a couple of reasons:
First of all, for me, the call to recvfrom returns 0, even though the buffer actually is populated with the response from the monitor.
I'm not sure about this one. The recvfrom is called in a loop, and POSIX says that recvfrom shall return the size if a message was read, or 0 if no messages were available but the other end of the connection did an orderly shutdown. I think we need a bit more understanding of why you are getting a 0 return, and whether it only happens after a successful iteration of the loop (in which case the contents of res are leftover from the prior iteration).
At any rate, the only way I can get anything useful to happen here is to completely remove the check, so this patch does just that.
In other words, maybe the better thing to do is add an earlier check: if (nbytes == 0) break; but I'm not sure of that idea, either, without more understanding of the root cause. -- Eric Blake eblake@redhat.com +1-801-349-2682 Libvirt virtualization library http://libvirt.org