[matei@localhost qemu-vm]$ sudo make
./create_net.sh tap0
+ device=tap0
+ '[' tap0 = tap0 ']'
+ addr=172.20.0.1/24
+ '[' tap0 = tap1 ']'
+ ip link show dev tap0
./create_net.sh tap1
+ device=tap1
+ '[' tap1 = tap0 ']'
+ '[' tap1 = tap1 ']'
+ addr=172.30.0.1/24
+ ip link show dev tap1
./nttcp -v -i &
qemu-system-i386 -cdrom boot.iso -boot d \
	-serial pipe:pipe1 -serial pipe:pipe2 \
	-hda disk1.img -hdb disk2.img \
	-s \
	-net nic,model=pcnet,vlan=0 -net tap,ifname=tap0,vlan=0,script=no,downscript=no \
	-net nic,model=i82559er,vlan=1 -net tap,ifname=tap1,vlan=1,script=no,downscript=no
nttcp-l: nttcp, version 1.47
nttcp-l: running in inetd mode on port 5037 - ignoring options beside -v and -p
bind: Cannot assign requested address
nttcp-l: service-socket: bind:: Cannot assign requested address, errno=99
qemu-system-i386: pci_add_option_rom: failed to find romfile "pxe-eepro100.rom"

(qemu-system-i386:2457): GLib-GObject-WARNING **: g_object_weak_unref: couldn't find weak ref 0x7fec8b1fa470(0x7fec9da81a60)

(qemu-system-i386:2457): GLib-GObject-WARNING **: g_object_weak_unref: couldn't find weak ref 0x7fec8b1fa470(0x7fec9da81a60)
[matei@localhost qemu-vm]$