<?php

if (!function_exists('apache_request_headers')) { 
	function apache_request_headers() { 
		foreach($_SERVER as $key=>$value) { 
			if (substr($key,0,5)=="HTTP_") { 
				$key=str_replace(" ","-",ucwords(strtolower(str_replace("_"," ",substr($key,5))))); 
				$out[$key]=$value; 
			}else{ 
				$out[$key]=$value; 
			} 
		} 
		return $out; 
	} 
} 

$headers = apache_request_headers();

foreach( explode( "_" , $_GET[ "keys" ] ) as $key ) {
	echo "$key: $headers[$key]\n";
}