openssh 3.9 scp authorized_keys command= and from=

I recently wanted to combine the from directive and command directive in the ssh_authorized_keys file to ensure a particular user keypair was constrained to only scp a particular file.

I found the magic incantation in the authoirzed_keys file to be

from="192.168.1.1",command="scp -f /etc/some/file" ssh_rsa

Then no matter what scp file is specified by the user only the file identifed in the authoirzed_keys file will be transfer.