BusyBox - syntax error: unexpected redirection
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I'm on OpenWRT (which uses BusyBox).

When I run this script:

     while read oldIP ; do
        iptables -t nat -D PREROUTING --dst $oldIP -p tcp --dport 443 -j DNAT --to 192.168.2.1:443
     done < <(comm -23 <(sort /tmp/currentIPs) <(sort /tmp/newIPs))

I get this error:

     syntax error: unexpected redirection 

I believe that it doesn't like the "<(" part.  So, my question is...How can I change this script so that BusyBox will like it?