Now I create a small PHP Application, here I have problem for using file path, because in Windows use this type location C:\Some\Location\index but in Linux /www/app/index so when I define the path using this / but when the application run in window machine it should be problem for this /.
So here I want to define the DIRECTORY_SEPARATOR both Windows and Linux platform.
PHP accepts both
\and/as valid path separators in all OS. So just use/in your code