Initial commit

README.org

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+Send MAC addrs of all current DHCP leases to <TODO>. Transmit only if
+the list changed since last transmission.

src/update_hacker_density

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+#!/bin/sh
+
+LeaseFile=/tmp/dhcp.leases
+TmpFile=/tmp/hackers
+StateFile=/tmp/hackers.md5
+Hash=md5sum
+
+awk '{ if ($1 > '$(date +%s)') print $2 }' < $LeaseFile > $TmpFile
+OldHash=$(cat $StateFile 2>/dev/null)
+NewHash=$($Hash $TmpFile | cut -f1 -d" ")
+if [ "$OldHash" != "$NewHash" ]; then
+	# send new state, update local state only if transmission was succesful
+	(	echo Es sind $(wc -l <$TmpFile) Hacker im Space:
+		cat $TmpFile) \
+	|  nc -c feinsterfug.de 666 \
+	&& echo "$NewHash" > $StateFile
+fi