go to "/folder/php/file.php" only with "/php/file.php" [htaccess]

I need my form to send the POST to file / php / login.phpbut I do not want to write "action =" file / ... ", I would like to leave this file (file) hidden in the HTML.

If someone has a teaching link .htaccessI would be grateful to you, because those I meet or do not have much, or write without explaining absolutely nothing.