#!/bin/sh
# Usage: addr [<if>]
# Show IPv4 address for interface <if> or all interfaces with
# no <if> given.

# Darwin/OSX
ifconfig -a        |
grep 'inet '       |
grep broadcast     |
awk '{ print $2 }'

# Linux
ifconfig -a        |
grep 'inet '       |
grep Bcast         |
awk '{ print $2 }'