You can write a script that only return the IP like:
/sbin/ifconfig eth0 | grep 'inet addr' | cut -d: -f2 | awk '{print $1}'
For MAC:
ifconfig | grep "inet " | grep -v 127.0.0.1 | cut -d -f2
Or for linux system
hostname -i | awk '{print $3}' # Ubuntu
hostname -i # Debian
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