Script to find ips from a text file (not working)

I have a set of domains (100+ inserted into a text file (like below) which I would like to get output the ip addresses associated with the domain name.

http://www.hippocampe.info/
http://www.highlighthealth.info/
http://www.helpindex.co.uk/
...

Here is what I've done so far but its not working so well..

<?php
$myFile = ("http://automax.tv/1000-3000.txt");
$handle = fopen("http://automax.tv/1000-3000.txt","r");
$data = fgets($handle);
$ip = rtrim(`/usr/bin/dig -4  $data +short`);
echo  $ip;
fclose($handle);
?>

Code (markup):

However its printing out the full dig without +short and not printing out the ip either.
http://www.automax.tv/checkip2.php
I need it to output every domain also.

If you enter dig -4 +short www.hippocampe.info it should give just the ip...

any ideas.

 

$ cat test.php
<?php
$s = "http://www.hippocampe.info/
http://www.highlighthealth.info/
http://www.helpindex.co.uk/";
$s = str_replace('/','',$s); $s = str_replace('http:','',$s); $l = explode("\n",$s);
foreach ($l as $h) {
   echo gethostbyname($h)."\n"; // change to echo $h.'  '.gethostbyname($h)."\n"; if you want to show the domain too
}
?>

Code (markup):

$ php test.php
91.186.0.7
69.163.230.6
87.117.195.168

Code (markup):

 

<?php

$file = file_get_contents('http://automax.tv/1000-3000.txt');

$lines = str_replace(array("\r\n", "\r"), "\n", $file);

$urls = explode("\n", $lines);

foreach($urls as $url){

echo $url." - ".gethostbyname($url)."<br>";
}

?>

PHP:

 

thanks danx10 that works perfectly and is just what I needed!
I like how you referenced the variables to php site.

xtra thanks