Australia photo & PC memo

function autoLink($str){
   $prefix = "([[:space:]]|\(|^)";
   $suffix = "([[:space:]]|\))";

   $linkPtns = array();
   $linkPtns[] = array("([-a-z0-9_.]+@[-a-z0-9_.]+)",
                     "\\1\\2\\3");
   $linkPtns[] = array("(http://|https://|ftp://)([[:alnum:]\+\$\;\?\.%,!#~*/:@&=_-]+)",
                     "\\1\\2\\3\\4");
   $linkPtns[] = array("(www\.[[:alnum:]\+\$\;\?\.%,!#~*/:@&=_-]+)",
                     "\\1\\2\\3");
   $linkPtns[] = array("([[:alnum:]/_-]+)(\.jpg|\.gif|\.png)",
                     "\\1\\4");

   foreach($linkPtns as $patterns)
   {
       $str = eregi_replace($prefix.$patterns[0].$suffix, $patterns[1], $str);
   }

   return $str;
}

//不正な記号をHTML特殊文字（html entity）に変換する
function allHtmlentities($str)
{
   // somehow can't convert em dash and en dash...
   $new_string = preg_replace(
      '/([^\x09\x0A\x0D\x20-\x7F]|[\x3A-\x40])/e',
      '"&#".ord("$0").";"',
      $str);
	return $new_string;
}