#eth0 ip

regular usage

$ifconfig

eth0  blob blob

lo     blob blob

wlan blob blob

try something better like this

udhayakumar@TB013:~$ ifconfig eth0 | grep "inet addr:"

          inet addr:192.168.0.117  Bcast:192.168.0.255  Mask:255.255.255.0

udhayakumar@TB013:~$ ifconfig wlan | grep "inet addr:"

          inet addr:192.168.0.119  Bcast:192.168.0.255  Mask:255.255.255.0

udhayakumar@TB013:~$ 

now How to use these things in php code

<?php

echo exec('/sbin/ifconfig eth0 | grep "inet addr:"');

echo "<br />";

echo  "wlan ip address::::: ";

echo 

exec('/sbin/ifconfig wlan | grep "inet addr:"');

?>