[libvirt] changing files in /var/lib/libvirt/images

Assume I am working with virtual disk image files in /var/lib/libvirt/images such as removing a file, defining a new file (with qemi-img create or qemu-img convert), or simply copying a file ("cp") from elsewhere such as VMware. When I do this, Guest definition or adding hardware to an existing guest under virt- manager does not "see" the file change. That is, until I terminate virt- manager and restart /etc/init.d/libvirtd. Is there some better/easier/less-disruptive means of notifying "whatever" that the list of files has changed? I noticed that /etc/init.d/libvirtd force-reload has no effect. I also notice that restarting libvirtd and/or terminating and restarting virt- manager while there are guests running really screws things up. If such a "means" does not exist, should one be created? [should this be an RFE in bugzilla?] Gene