If the link_id is not specified, mysql_close() will close the most recently opened link.
The syntax is: int mysql_close ([int link_id])
@mysql_connect("localhost", "web", "asdf") or die("Could not connect to MySQL server!");
@mysql_select_db("company") or die("Could not select company database!");
print "You're connected to a MySQL database!";
mysql_close();
?>