Rewriting -net to new style syntax?

[Ede Wolf]

Hello,

Reading, that -net is deprecated and in this case not working any more, 
I am trying to rewrite a network config in the -netdev/-device syntax. 
However, I am failing to convert:

-net nic,model=virtio,macaddr=02:.. -net tap,fd=3 3<>/dev/tap9


I've tried to put the filedescriptor in different places:

 -netdev tap,[fd=3 3<>/dev/tap9,]id=macvtap,[ifname=fd=3 
<>/dev/tap9,]script=no,downscript=no,vhost=on\
 -device virtio-net,netdev=macvtap,mac=02:...\

 But I am always ending up with something like:

 qemu-system-x86_64: 3<>/dev/tap9,id=macvtap,script=no,downscript=no: 
Could not open '3<>/dev/tap9,id=macvtap,script=no,downscript=no': No 
such file or directory

 Needless to say, /dev/tap9 is existent and has the proper permissions

 Any ideas or documentation that shed some light onto this?

 Thanks

 Ede