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$a = $_SERVER['HTTP_HOST'] // server-name - domain
$b = $_SERVER['PHP_SELF'] // you're page, as you know
$c = $_SERVER['QUERY_STRING'] // everything after the "?",
// but not including the "?"

echo "$a$b?$c";  // would print whole URL

$d = $_SERVER['HTTP_HOST'].$_SERVER['PHP_SELF']."?".$_SERVER['QUERY_STRING'];
// notice the "?" in middle of the above, and variables seprated by dots(.)
// $_SERVER['QUERY_STRING'] reads url GET query, but does not contain
// the "?" in it itself, since "?" is not a variable.

echo $d; // would print the whole URL using above.

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