Checks whether a file or directory exists.
Path to the file or directory.
On windows, use //computername/share/filename or \\computername\share\filename to check files on network shares.
Returns true if the file or directory specified by filename exists; false otherwise.
This function will return false for symlinks pointing to non-existing files.
The check is done using the real UID/GID instead of the effective one.
Because PHP's integer type is signed and many platforms use 32bit integers, some filesystem functions may return unexpected results for files which are larger than 2GB.
Exceptions and Errors
Upon failure, an E_WARNING is emitted.
The results of this function are cached. See clearstatcache for more details.
As of PHP 5.0.0, this function can also be used with some URL wrappers. Refer to to determine which wrappers support stat family of functionality.