Simple solution to a directory relative uri

Simple solution to a directory relative uri

queestion is:
is there some kind of prebuilt function that can get the uri requested
relative to a server directory.
im gonna be doing some routing but i dont have any of the files for that
on the root (localhost/htdocs)
instead i have them here (localhost/htdocs/Mvc/*files here (index,models
folder ect)*
i want the Uri thats requested as if the folder Mvc was root example
localhost/Mvc/index.php?action=login
i want the action-login part.
I know i coud work some string action just want to know if there is a
simpler way or a premade function in the LIbS for this
I do for the sake of learning and becoming a better developer so plz ntn
about the 101 overly complicated frameworks already built. Thanks in
advance