Echo a list of all bound IPs. If an IP is passed, echo that IP if it is currently bound.

isip.sh

#!/bin/bash

# Tested in OS X 10.5
#
# Echo a list of all bound IPs. If an IP is passed, echo that
# IP if it is currently bound.

IPLIST=$(ifconfig -u | grep -w 'inet' | grep -v '127[.]0[.]0[.]1' | cut -d ' ' -f 2 | sed 's/^ *//;s/ *$//')

if [ $1 ]; then
  if [ -n "$(echo $IPLIST | grep -w $1)" ]; then
    echo $1
  fi
else
  echo $IPLIST
fi