I’m frequently firing up tcpdump on my mac, but then having to restart it with the correct interface if I happened to be on a wireless network (which I frequently am on the mac). I finally got tired of that, so I whipped up a quick script that determines which interface is up and consequently starts tcpdump on that interface. Allow me to cat /usr/bin/stcpdump for you:
{% codeblock %}#!/bin/shMuch better - saves me a big of grief. ;o)INT=
ifconfig | grep -A3 "en.:" | grep -B2 inet\ | head -n 1 | cut -f1 -d:sudo tcpdump -i $INT $@{% endcodeblock %}