How does this option function to set a network? The acp.domain option is a convoluted decimal representation of the network portion of the IP address used for acp.
toaster*> options acp
acp.domain 65193
acp.enabled on
acp.netmask 65535
acp.port e0f
Take 65193 and convert it to binary: 1111111010101001. Then split it up into two (or more) octets: 11111110 10101001. Then convert each of the octets back to decimal: 254 169. Then reverse the order: 169 254. That is the acp network. The netmask portion is more straightforward. In this case our ACP network is 169.254/16.
You could hack a quick little one liner:
# for i in `echo "obase=2;65193" |bc | awk 'BEGIN{FS=""} {for(i=1;i<33;i++){printf $i; if(i==8)printf " ";}printf "\n"}'`; do echo "ibase=2;$i" |bc; done|tac | paste - - | sed 's/\t/./'
169.254
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