Re: [Libvir] RFC [0/3]: Re-factor QEMU daemon protocol to use XDR

Daniel P. Berrange wrote: >On Wed, Apr 11, 2007 at 01:01:30PM +0100, Richard W.M. Jones wrote: >>I don't think those patches got memory allocation / deallocation of XDR >>structures right. Not surprising really since it's totally >>undocumented! In a bid to rectify this, I have documented how to do it >>here: >> >>http://et.redhat.com/~rjones/xdr_tests/ > >Nice. BTW on the subject of record streams - xdrrec_create - while very >nice looking on the surface, it is utterly useless because the impl >relies on the underlying FD / socket being in blocking mode. If you use >non-blocking sockets marshalling/de-marshalling will fail on the first >-EAGAIN the routines see, and they have no way to restart where they >left off. This is why I serialized to/from a xdrmem buffer, and then used >my own read/write code to send to the socket where I could correctly deal >with non-blocking mode. Oh right - that totally passed me by. When are you using non-blocking sockets? I was under the impression they were all blocking in qemu_internal / libvirt_qemud.