[libvirt] iface-list command in virsh

Hi, I'm trying to list physical interface of a remote tcp host via the C API and it fails. I have tried to use virsh iface-list in remote TCP connection and it fails also. I have trying on the libvirt host with my normal account and it fails also, but when I connect under root account on the libvirt host, iface-list works. Any clue ? Best regards, Arnaud Champion