External Links Prompt

[viper2843]

I am trying to write a script that checks all links clicked on my site and if the address is to an external site than open a window and warn the user that they are going away from the site. Since I am new at PHP I don't exactly know where to start. The server has global variables on so I was thinking about using HTTP_SERVER_VARS. I need some direction as to where to start. Thanks.

[Pig]

function make_a($link, $link_text="")
{
     if( strstr($link, "mydomainname.com") )
     {
          if( empty($link) ) $out = "<a href='$link'>$link</a>";
          else $out = "<a href='$link'>$link_text</a>";
     }
     else
     {
          if( empty($link) ) $out = "<a href='$link' target=_blank>$link</a>";
          else $out = "<a href='$link' target=_blank>$link_text</a>";
     }
}