I add a rule:
VBoxManage modifyvm "xp" --natpf1 "guestrdp,tcp,127.0.0.1,33890,,3389"
I list it:
VBoxManage showvminfo "xp" | awk '/NIC/ && /Rule/ {print}'
NIC 1 Rule(0): name = guestrdp, protocol = tcp, host ip = 127.0.0.1, host port = 33890, guest ip = , guest port = 3389
But how can I delete it?