How to get all urls from page (php)

Question

I have a page with urls with descriptions listed one under another (something like bookmarks/list of sites). How do I use php to get all urls from that page and write them to txt file (one per line, only url without description)?

Page looks like this:

Some description

Other description

Another one

And I would like script's txt output to look like this:

http://link.com

http://link2.com

http://link3.com

Answer 1

one way

$url="http://wwww.somewhere.com";
$data=file_get_contents($url);
$data = strip_tags($data,"<a>");
$d = preg_split("/<\/a>/",$data);
foreach ( $d as $k=>$u ){
    if( strpos($u, "<a href=") !== FALSE ){
        $u = preg_replace("/.*<a\s+href=\"/sm","",$u);
        $u = preg_replace("/\".*/","",$u);
        print $u."\n";
    }
}