How To Get Full Url From Address Bar

thanks for your previous help on other posts. but now i have a challenge that i have not been able to resolve. i am writing a php script and i am required to get the full url from the current page. and not the domain only like using the hostname, but rather the whole url. can you help me get complete url in php? if i can get the get full path using php that would be very helpful. i know its probably easy like getting it from the server path or using javascript, but i want to use php because the script i am using i have to use a string. anyways, thanks in advance. i looked everywhere in php.net to see if a function exists that i can use to grab the url from the browsers address bar, so if you know of any function or class, let me know