Akio Takebe wrote: > Hi, > > AFAIK kvm has only an interface of qemu console when we use device > hotplug, migration and so on. How does libvirt access the interface > of qemu console? > As far as I understand it (from looking at the code recently), you can tell the qemu monitor to open against a pty. libvirtd does this, and holds on to the other end of the pty, and then issues commands through the PTY to do anything that you need through the monitor interface. Look at src/qemu_driver.c:qemudWaitForMonitor() (or thereabouts) for where this is setup while starting a domain.